Biblioteca para criação simples e rápida de programas para MetaTrader (Parte XXXIII): solicitações de negociação pendentes, fechamento de posições por condições

Artyom Trishkin | 29 abril, 2020

Sumário

• Ideia
• Implementação
• Teste
• O que vem agora?
  

Continuamos a trabalhar na funcionalidade da biblioteca para negociar usando solicitações pendentes. Nós já implementamos o envio de solicitações pendentes segundo condições para abrir posições e definir ordens pendentes. Agora, complementamos a funcionalidade fechando as posições por meio de condições que especificaremos. Criaremos três tipos de fechamento de posições: total, parcial e mediante posição oposta.

Ideia

À medida que criamos uma funcionalidade completa de biblioteca para negociar com ajuda de solicitações pendentes, gradualmente detectamos gargalos, situações erradas e defeitos, para depois, graças a isso, corrigirmos a lógica deficiente ou os métodos errôneos.

Nesse contexto, por exemplo, para determinar corretamente que uma solicitação pendente já foi ativada e precisa ser excluída, verificamos o último evento de negociação na conta: quando os dados registrados no objeto-solicitação pendente coincidem com o último evento, consideramos que a solicitação já foi disparada e removida. Porém, acontece que essa lógica nem sempre é correta. Por exemplo, ao fechar parcialmente posições usando solicitações pendentes, quando resta fechar a última parte da posição aberta (o fechamento anterior é de 0,01 lotes e a parte restante também é de 0,01 lotes), o método para verificar se a solicitação é relevante considera que ela já foi disparada, já que seus dados coincidem com o fechamento anterior.

Enquanto pensava em como manejar essa situação, cheguei à conclusão de que é mais fácil verificar o último evento de negociação apenas quando o evento de negociação ocorrido é registrado na conta, em vez de rastrear a hora de criação do evento e a que corresponde à execução da solicitação de negociação ou realizar outras verificações de controle. Felizmente, já implementamos isso há muito tempo, e podemos usar o método da classe de eventos que retorna o sinalizador que serve para indicar se existe um novo evento na conta. Quando isso acontecer, não confundiremos o evento anterior com o atual, já que a verificação ocorre apenas no momento em que o novo evento é corrigido (imediatamente após).

Como as solicitações de negociação pendentes no futuro podem fazer parte da funcionalidade da estratégia de negociação, é aconselhável ter acesso a todos os objetos-solicitações pendentes criados que aguardam até serem atendidas suas condições de ativação. Para facilitar a seleção e classificação dos objetos desejados, adicionamos um recurso para pesquisar e classificar com base nas propriedades dos objetos-solicitações pendentes na lista de solicitações. Como resultado, isso permitirá, com ajuda da GUI, selecionar exibir e classificar no programa os objetos requeridos e gerenciá-los (alterar, excluir e modificar).

Implementação

Ao construtor da classe de solicitação pendente abstrata contida no arquivo PendRequest.mqh adicionamos a inicialização (redefinimos todos os campos) da estrutura da solicitação de negociação:

//+------------------------------------------------------------------+
//| Constructor                                                      |
//+------------------------------------------------------------------+
CPendRequest::CPendRequest(const ENUM_PEND_REQ_STATUS status,
                           const uchar id,
                           const double price,
                           const ulong time,
                           const MqlTradeRequest &request,
                           const int retcode)
  {
   ::ZeroMemory(this.m_request);
   this.CopyRequest(request);
   this.m_is_hedge=#ifdef __MQL4__ true #else bool(::AccountInfoInteger(ACCOUNT_MARGIN_MODE)==ACCOUNT_MARGIN_MODE_RETAIL_HEDGING) #endif;
   this.m_digits=(int)::SymbolInfoInteger(this.GetProperty(PEND_REQ_PROP_MQL_REQ_SYMBOL),SYMBOL_DIGITS);
   int dg=(int)DigitsLots(this.GetProperty(PEND_REQ_PROP_MQL_REQ_SYMBOL));
   this.m_digits_lot=(dg==0 ? 1 : dg);
   this.SetProperty(PEND_REQ_PROP_STATUS,status);
   this.SetProperty(PEND_REQ_PROP_ID,id);
   this.SetProperty(PEND_REQ_PROP_RETCODE,retcode);
   this.SetProperty(PEND_REQ_PROP_TYPE,this.GetProperty(PEND_REQ_PROP_RETCODE)>0 ? PEND_REQ_TYPE_ERROR : PEND_REQ_TYPE_REQUEST);
   this.SetProperty(PEND_REQ_PROP_TIME_CREATE,time);
   this.SetProperty(PEND_REQ_PROP_PRICE_CREATE,price);
   this.m_pause.SetTimeBegin(this.GetProperty(PEND_REQ_PROP_TIME_CREATE));
   this.m_pause.SetWaitingMSC(this.GetProperty(PEND_REQ_PROP_WAITING));
   ::ArrayResize(this.m_activated_control,0,10);
   this.m_follow=true;
  }
//+------------------------------------------------------------------+

Ao não redefinir todos os campos da estrutura, em alguns casos, era criado um tipo incorreto de solicitação pendente, pois quando se cria um objeto para fechamento de posição e o campo position_by na estrutura da solicitação de negociação é diferente de zero, é criado um objeto-solicitação pendente para fechamento de posição mediante uma oposta. Ao não redefinir os campos preliminarmente, às vezes era criada uma solicitação para fechamento de posição mediante uma oposta, em vez do simples fechamento de posição. No entanto, isso está certo, pois nunca se pode esperar que uma simples declaração de variável sem inicializá-la posteriormente não leve a resultados imprevisíveis. Foi isso que aconteceu quando esqueci de inicializar a estrutura da solicitação de negociação no construtor da classe.

Na seção pública da classe de gerenciamento de negociação contida no arquivo PendReqControl.mqh, declaramos dois métodos:
um cria uma solicitação pendente para fechamento total e parcial de posição e outro para fechamento mediante posição oposta:

public:
//--- Return itself
   CTradingControl     *GetObject(void)            { return &this;   }
//--- Timer
   virtual void         OnTimer(void);
//--- Constructor
                        CTradingControl();
//--- (1) Create a pending request (1) to open a position, (2) to place a pending order
   template<typename SL,typename TP> 
   int                  CreatePReqPosition(const ENUM_POSITION_TYPE type,
                                        const double volume,
                                        const string symbol,
                                        const ulong magic=ULONG_MAX,
                                        const SL sl=0,
                                        const TP tp=0,
                                        const uchar group_id1=0,
                                        const uchar group_id2=0,
                                        const string comment=NULL,
                                        const ulong deviation=ULONG_MAX,
                                        const ENUM_ORDER_TYPE_FILLING type_filling=WRONG_VALUE);
   template<typename PS,typename PL,typename SL,typename TP>
   int                  CreatePReqOrder(const ENUM_ORDER_TYPE order_type,
                                        const double volume,
                                        const string symbol,
                                        const PS price_set,
                                        const PL price_limit=0,
                                        const SL sl=0,
                                        const TP tp=0,
                                        const ulong magic=ULONG_MAX,
                                        const uchar group_id1=0,
                                        const uchar group_id2=0,
                                        const string comment=NULL,
                                        const datetime expiration=0,
                                        const ENUM_ORDER_TYPE_TIME type_time=WRONG_VALUE,
                                        const ENUM_ORDER_TYPE_FILLING type_filling=WRONG_VALUE);
//--- Create a pending request (1) for full and partial position closure, (2) for closing a position by an opposite one
   int                  CreatePReqClose(const ulong ticket,const double volume=WRONG_VALUE,const string comment=NULL,const ulong deviation=ULONG_MAX);
   int                  CreatePReqCloseBy(const ulong ticket,const ulong ticket_by);
   
//--- Set pending request activation criteria
   bool                 SetNewActivationProperties(const uchar id,
                                                   const ENUM_PEND_REQ_ACTIVATION_SOURCE source,
                                                   const int property,
                                                   const double control_value,
                                                   const ENUM_COMPARER_TYPE comparer_type,
                                                   const double actual_value);
  };
//+------------------------------------------------------------------+

No método para verificar a relevância de uma solicitação pendente, modificamos o bloco para processar objetos-solicitações pendentes ao fechar posições parcialmente ou mediante uma oposta:

//+------------------------------------------------------------------+
//| Checking the pending request relevance                           |
//+------------------------------------------------------------------+
bool CTradingControl::CheckPReqRelevance(CPendRequest *req_obj,const MqlTradeRequest &request,const int index)
  {
//--- If this is a position opening or placing a pending order
   if((req_obj.Action()==TRADE_ACTION_DEAL && req_obj.Position()==0) || req_obj.Action()==TRADE_ACTION_PENDING)
     {
      //--- Get the pending request ID
      uchar id=this.GetPendReqID((uint)request.magic);
      //--- Get the list of orders/positions containing the order/position with the pending request ID
      CArrayObj *list=this.m_market.GetList(ORDER_PROP_PEND_REQ_ID,id,EQUAL);
      if(::CheckPointer(list)==POINTER_INVALID)
         return false;
      //--- If the order/position is present, the request is handled: remove it and proceed to the next (leave the method for the external loop)
      if(list.Total()>0)
        {
         if(this.m_log_level>LOG_LEVEL_NO_MSG)
            ::Print(req_obj.Header(),": ",CMessage::Text(MSG_LIB_TEXT_PEND_REQUEST_EXECUTED));
         this.m_list_request.Delete(index);
         return false;
        }
     }
//--- Otherwise: full and partial position closure, removing an order, modifying order parameters and position stop orders
   else
     {
      CArrayObj *list=NULL;
      //--- if this is a position closure, including a closure by an opposite one
      if((req_obj.Action()==TRADE_ACTION_DEAL && req_obj.Position()>0) || req_obj.Action()==TRADE_ACTION_CLOSE_BY)
        {
         //--- Get a position with the necessary ticket from the list of open positions
         list=this.m_market.GetList(ORDER_PROP_TICKET,req_obj.Position(),EQUAL);
         if(::CheckPointer(list)==POINTER_INVALID)
            return false;
         //--- If the market has no such position, the request is handled: remove it and proceed to the next (leave the method for the external loop)
         if(list.Total()==0)
           {
            if(this.m_log_level>LOG_LEVEL_NO_MSG)
               ::Print(req_obj.Header(),": ",CMessage::Text(MSG_LIB_TEXT_PEND_REQUEST_EXECUTED));
            this.m_list_request.Delete(index);
            return false;
           }
         //--- Otherwise, if the position still exists, this is a partial closure
         else
           {
            //--- If there is an event
            if(this.m_events.IsEvent())
              {
               //--- Get the list of all account trading events
               list=this.m_events.GetList();
               if(list==NULL)
                  return false;
               //--- In the loop from the end of the account trading event list
               int events_total=list.Total();
               for(int j=events_total-1; j>WRONG_VALUE; j--)
                 {
                  //--- get the next trading event
                  CEvent *event=list.At(j);
                  if(event==NULL)
                     continue;
                  //--- If this event is a partial closure or there was a partial closure when closing by an opposite one
                  if(event.TypeEvent()==TRADE_EVENT_POSITION_CLOSED_PARTIAL || event.TypeEvent()==TRADE_EVENT_POSITION_CLOSED_PARTIAL_BY_POS)
                    {
                     //--- If a position ticket in a trading event coincides with the ticket in a pending trading request
                     if(event.TicketFirstOrderPosition()==req_obj.Position())
                       {
                        //--- Get a position object from the list of market positions
                        CArrayObj *list_orders=this.m_market.GetList(ORDER_PROP_TICKET,req_obj.Position(),EQUAL);
                        if(list_orders==NULL || list_orders.Total()==0)
                           break;
                        COrder *order=list_orders.At(list_orders.Total()-1);
                        if(order==NULL)
                           break;
                        //--- Set actual position data to the pending request object
                        this.SetOrderActualProperties(req_obj,order);
                        //--- If (executed request volume + unexecuted request volume) is equal to the requested volume in a pending request -
                        //--- the request is handled: remove it and break the loop by the list of account trading events
                        if(req_obj.GetProperty(PEND_REQ_PROP_MQL_REQ_VOLUME)==event.VolumeOrderExecuted()+event.VolumeOrderCurrent())
                          {
                           if(this.m_log_level>LOG_LEVEL_NO_MSG)
                              ::Print(req_obj.Header(),": ",CMessage::Text(MSG_LIB_TEXT_PEND_REQUEST_EXECUTED));
                           this.m_list_request.Delete(index);
                           break;
                          }
                       }
                    }
                 }
               //--- If a handled pending request object was removed by the trading event list in the loop, move on to the next one (leave the method for the external loop)
               if(::CheckPointer(req_obj)==POINTER_INVALID)
                  return false;
              }
           }
        }
      //--- If this is a modification of position stop orders
      if(req_obj.Action()==TRADE_ACTION_SLTP)
        {
         //--- Get the list of all account trading events
         list=this.m_events.GetList();
         if(list==NULL)
            return false;
         //--- In the loop from the end of the account trading event list
         int events_total=list.Total();
         for(int j=events_total-1; j>WRONG_VALUE; j--)
           {
            //--- get the next trading event
            CEvent *event=list.At(j);
            if(event==NULL)
               continue;
            //--- If this is a change of the position's stop orders
            if(event.TypeEvent()>TRADE_EVENT_MODIFY_ORDER_TP)
              {
               //--- If a position ticket in a trading event coincides with the ticket in a pending trading request
               if(event.TicketFirstOrderPosition()==req_obj.Position())
                 {
                  //--- Get a position object from the list of market positions
                  CArrayObj *list_orders=this.m_market.GetList(ORDER_PROP_TICKET,req_obj.Position(),EQUAL);
                  if(list_orders==NULL || list_orders.Total()==0)
                     break;
                  COrder *order=list_orders.At(list_orders.Total()-1);
                  if(order==NULL)
                     break;
                  //--- Set actual position data to the pending request object
                  this.SetOrderActualProperties(req_obj,order);
                  //--- If all modifications have worked out -
                  //--- the request is handled: remove it and break the loop by the list of account trading events
                  if(req_obj.IsCompleted())
                    {
                     if(this.m_log_level>LOG_LEVEL_NO_MSG)
                        ::Print(req_obj.Header(),": ",CMessage::Text(MSG_LIB_TEXT_PEND_REQUEST_EXECUTED));
                     this.m_list_request.Delete(index);
                     break;
                    }
                 }
              }
           }
         //--- If a handled pending request object was removed by the trading event list in the loop, move on to the next one (leave the method for the external loop)
         if(::CheckPointer(req_obj)==POINTER_INVALID)
            return false;
        }
      //--- If this is a pending order removal
      if(req_obj.Action()==TRADE_ACTION_REMOVE)
        {
         //--- Get the list of removed pending orders from the historical list
         list=this.m_history.GetList(ORDER_PROP_STATUS,ORDER_STATUS_HISTORY_PENDING,EQUAL);
         if(::CheckPointer(list)==POINTER_INVALID)
            return false;
         //--- Leave a single order with the necessary ticket in the list
         list=CSelect::ByOrderProperty(list,ORDER_PROP_TICKET,req_obj.Order(),EQUAL);
         //--- If the order is present, the request is handled: remove it and proceed to the next (leave the method for the external loop)
         if(list.Total()>0)
           {
            if(this.m_log_level>LOG_LEVEL_NO_MSG)
               ::Print(req_obj.Header(),": ",CMessage::Text(MSG_LIB_TEXT_PEND_REQUEST_EXECUTED));
            this.m_list_request.Delete(index);
            return false;
           }
        }
      //--- If this is a pending order modification
      if(req_obj.Action()==TRADE_ACTION_MODIFY)
        {
         //--- Get the list of all account trading events
         list=this.m_events.GetList();
         if(list==NULL)
            return false;
         //--- In the loop from the end of the account trading event list
         int events_total=list.Total();
         for(int j=events_total-1; j>WRONG_VALUE; j--)
           {
            //--- get the next trading event
            CEvent *event=list.At(j);
            if(event==NULL)
               continue;
            //--- If this event involves any change of modified pending order parameters
            if(event.TypeEvent()>TRADE_EVENT_TRIGGERED_STOP_LIMIT_ORDER && event.TypeEvent()<TRADE_EVENT_MODIFY_POSITION_SL_TP)
              {
               //--- If an order ticket in a trading event coincides with the ticket in a pending trading request
               if(event.TicketOrderEvent()==req_obj.Order())
                 {
                  //--- Get an order object from the list
                  CArrayObj *list_orders=this.m_market.GetList(ORDER_PROP_TICKET,req_obj.Order(),EQUAL);
                  if(list_orders==NULL || list_orders.Total()==0)
                     break;
                  COrder *order=list_orders.At(0);
                  if(order==NULL)
                     break;
                  //--- Set actual order data to the pending request object
                  this.SetOrderActualProperties(req_obj,order);
                  //--- If all modifications have worked out -
                  //--- the request is handled: remove it and break the loop by the list of account trading events
                  if(req_obj.IsCompleted())
                    {
                     if(this.m_log_level>LOG_LEVEL_NO_MSG)
                        ::Print(req_obj.Header(),": ",CMessage::Text(MSG_LIB_TEXT_PEND_REQUEST_EXECUTED));
                     this.m_list_request.Delete(index);
                     break;
                    }
                 }
              }
           }
        }
     }
//--- Exit if the pending request object has been removed after checking its operation (leave the method for the external loop)
   return(::CheckPointer(req_obj)==POINTER_INVALID ? false : true);
  }
//+------------------------------------------------------------------+

Aqui adicionamos uma verificação para saber se em dado momento está definido o sinalizador que indica se na conta ocorreu algum evento. Dessa maneira, podemos sempre processar apenas o último evento de negociação e não afetar o anterior localizado na lista de eventos de negociação da conta, além disso, ele pode ser exatamente o mesmo que o atual e, caso seja assim, o objeto de solicitação pendente recém-criado é excluído imediatamente como se já tivesse sido ativado, o que nós não precisamos.

Fora do corpo da classe, escrevemos a implementação de métodos para criar solicitações pendentes que permitam o fechamento total e parcial da posição e o fechamento da posição por uma oposta:

//+------------------------------------------------------------------+
//| Create a pending request for closing a position                  |
//+------------------------------------------------------------------+
int CTradingControl::CreatePReqClose(const ulong ticket,const double volume=WRONG_VALUE,const string comment=NULL,const ulong deviation=ULONG_MAX)
  {
//--- If the global trading ban flag is set, exit and return WRONG_VALUE
   if(this.IsTradingDisable())
     {
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN,CMessage::Text(MSG_LIB_TEXT_TRADING_DISABLE));
      return WRONG_VALUE;
     }
//--- Set the error flag as "no errors"
   this.m_error_reason_flags=TRADE_REQUEST_ERR_FLAG_NO_ERROR;
   ENUM_ACTION_TYPE action=ACTION_TYPE_CLOSE;
//--- Get an order object by ticket
   COrder *order=this.GetOrderObjByTicket(ticket);
   if(order==NULL)
     {
      this.m_error_reason_flags=TRADE_REQUEST_ERR_FLAG_INTERNAL_ERR;
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN,CMessage::Text(MSG_LIB_SYS_ERROR_FAILED_GET_ORD_OBJ));
      return false;
     }
   ENUM_ORDER_TYPE order_type=(ENUM_ORDER_TYPE)order.TypeOrder();
//--- Get a symbol object by a position ticket
   CSymbol *symbol_obj=this.GetSymbolObjByPosition(ticket,DFUN);
   //--- If failed to get the symbol object, display the message and return 'false'
   if(symbol_obj==NULL)
     {
      this.m_error_reason_flags=TRADE_REQUEST_ERR_FLAG_INTERNAL_ERR;
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN,CMessage::Text(MSG_LIB_SYS_ERROR_FAILED_GET_SYM_OBJ));
      return false;
     }
//--- get a trading object from a symbol object
   CTradeObj *trade_obj=symbol_obj.GetTradeObj();
   if(trade_obj==NULL)
     {
      this.m_error_reason_flags=TRADE_REQUEST_ERR_FLAG_INTERNAL_ERR;
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN,CMessage::Text(MSG_LIB_SYS_ERROR_FAILED_GET_TRADE_OBJ));
      return false;
     }
//--- Update symbol quotes
   if(!symbol_obj.RefreshRates())
     {
      trade_obj.SetResultRetcode(10021);
      trade_obj.SetResultComment(CMessage::Text(trade_obj.GetResultRetcode()));
      this.AddErrorCodeToList(10021);  // No quotes to handle the request
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN,CMessage::Text(10021));
      return false;
     }
//--- Look for the least of the possible IDs. If failed to find, return WRONG_VALUE
   int id=this.GetFreeID();
   if(id<1)
     {
      //--- No free IDs to create a pending request
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN,CMessage::Text(MSG_LIB_TEXT_PEND_REQUEST_NO_FREE_IDS));
      return WRONG_VALUE;
     }

//--- Write a volume, deviation and a comment to the request structure
   this.m_request.deviation=(deviation==ULONG_MAX ? trade_obj.GetDeviation() : deviation);
   this.m_request.comment=(comment==NULL ? trade_obj.GetComment() : comment);
   this.m_request.volume=(volume==WRONG_VALUE || volume>order.Volume() ? order.Volume() : symbol_obj.NormalizedLot(volume));
//--- Write a magic number, a symbol name,
//--- a trading operation type, as well as order type and ticket to the request structure
   this.m_request.magic=order.Magic();
   this.m_request.symbol=symbol_obj.Name();
   this.m_request.action=TRADE_ACTION_DEAL;
   this.m_request.type=order_type;
   this.m_request.position=ticket;
   this.m_request.position_by=0;
//--- As a result of creating a pending trading request, return either its ID or -1 if unsuccessful
   if(this.CreatePendingRequest(PEND_REQ_STATUS_CLOSE,(uchar)id,1,ulong(END_TIME-(ulong)::TimeCurrent()),this.m_request,0,symbol_obj,order))
      return id;
   return WRONG_VALUE;
  }
//+--------------------------------------------------------------------+
//| Create a pending request for closing a position by an opposite one |
//+--------------------------------------------------------------------+
int CTradingControl::CreatePReqCloseBy(const ulong ticket,const ulong ticket_by)
  {
//--- If the global trading ban flag is set, exit and return WRONG_VALUE
   if(this.IsTradingDisable())
     {
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN,CMessage::Text(MSG_LIB_TEXT_TRADING_DISABLE));
      return WRONG_VALUE;
     }
//--- Set the error flag as "no errors"
   this.m_error_reason_flags=TRADE_REQUEST_ERR_FLAG_NO_ERROR;
   ENUM_ACTION_TYPE action=ACTION_TYPE_CLOSE_BY;
//--- Get an order object by ticket
   COrder *order=this.GetOrderObjByTicket(ticket);
   if(order==NULL)
     {
      this.m_error_reason_flags=TRADE_REQUEST_ERR_FLAG_INTERNAL_ERR;
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN,CMessage::Text(MSG_LIB_SYS_ERROR_FAILED_GET_ORD_OBJ));
      return false;
     }
   ENUM_ORDER_TYPE order_type=(ENUM_ORDER_TYPE)order.TypeOrder();
//--- Get a symbol object by a position ticket
   CSymbol *symbol_obj=this.GetSymbolObjByPosition(ticket,DFUN);
   if(symbol_obj==NULL)
     {
      this.m_error_reason_flags=TRADE_REQUEST_ERR_FLAG_INTERNAL_ERR;
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN,CMessage::Text(MSG_LIB_SYS_ERROR_FAILED_GET_SYM_OBJ));
      return false;
     }
//--- trading object of a closed position
   CTradeObj *trade_obj_pos=this.GetTradeObjByPosition(ticket,DFUN);
   if(trade_obj_pos==NULL)
     {
      this.m_error_reason_flags=TRADE_REQUEST_ERR_FLAG_INTERNAL_ERR;
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN_ERR_LINE,CMessage::Text(MSG_LIB_SYS_ERROR_FAILED_GET_TRADE_OBJ));
      return false;
     }
   if(!this.m_account.IsHedge())
     {
      trade_obj_pos.SetResultRetcode(MSG_ACC_UNABLE_CLOSE_BY);
      trade_obj_pos.SetResultComment(CMessage::Text(trade_obj_pos.GetResultRetcode()));
      return false;
     }
//--- check the presence of an opposite position
   if(!this.CheckPositionAvailablity(ticket_by,DFUN))
     {
      trade_obj_pos.SetResultRetcode(MSG_LIB_SYS_ERROR_POSITION_BY_ALREADY_CLOSED);
      trade_obj_pos.SetResultComment(CMessage::Text(trade_obj_pos.GetResultRetcode()));
      return false;
     }
//--- trading object of an opposite position
   CTradeObj *trade_obj_pos_by=this.GetTradeObjByPosition(ticket_by,DFUN);
   if(trade_obj_pos_by==NULL)
     {
      trade_obj_pos.SetResultRetcode(MSG_LIB_SYS_ERROR_FAILED_GET_TRADE_OBJ);
      trade_obj_pos.SetResultComment(CMessage::Text(trade_obj_pos.GetResultRetcode()));
      this.m_error_reason_flags=TRADE_REQUEST_ERR_FLAG_INTERNAL_ERR;
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN_ERR_LINE,CMessage::Text(MSG_LIB_SYS_ERROR_FAILED_GET_TRADE_OBJ));
      return false;
     }
//--- If a symbol of a closed position is not equal to an opposite position's one, inform of that and exit
   if(symbol_obj.Name()!=trade_obj_pos_by.GetSymbol())
     {
      trade_obj_pos.SetResultRetcode(MSG_LIB_TEXT_CLOSE_BY_SYMBOLS_UNEQUAL);
      trade_obj_pos.SetResultComment(CMessage::Text(trade_obj_pos.GetResultRetcode()));
      this.m_error_reason_flags=TRADE_REQUEST_ERR_FLAG_INTERNAL_ERR;
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN,CMessage::Text(MSG_LIB_TEXT_CLOSE_BY_SYMBOLS_UNEQUAL));
      return false;
     }
//--- Update symbol quotes
   if(!symbol_obj.RefreshRates())
     {
      trade_obj_pos.SetResultRetcode(10021);
      trade_obj_pos.SetResultComment(CMessage::Text(trade_obj_pos.GetResultRetcode()));
      this.AddErrorCodeToList(10021);  // No quotes to handle the request
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN,CMessage::Text(10021));
      return false;
     }
//--- Look for the least of the possible IDs. If failed to find, return WRONG_VALUE
   int id=this.GetFreeID();
   if(id<1)
     {
      //--- No free IDs to create a pending request
      if(this.m_log_level>LOG_LEVEL_NO_MSG)
         ::Print(DFUN,CMessage::Text(MSG_LIB_TEXT_PEND_REQUEST_NO_FREE_IDS));
      return WRONG_VALUE;
     }

//--- Write the trading operation type, symbol, tickets of two positions, type and volume of a closed position to the request structure
   this.m_request.action=TRADE_ACTION_CLOSE_BY;
   this.m_request.symbol=symbol_obj.Name();
   this.m_request.position=ticket;
   this.m_request.position_by=ticket_by;
   this.m_request.type=order_type;
   this.m_request.volume=order.Volume();
//--- As a result of creating a pending trading request, return either its ID or -1 if unsuccessful
   if(this.CreatePendingRequest(PEND_REQ_STATUS_CLOSE,(uchar)id,1,ulong(END_TIME-(ulong)::TimeCurrent()),this.m_request,0,symbol_obj,order))
      return id;
   return WRONG_VALUE;
  }
//+------------------------------------------------------------------+

Os métodos são idênticos a todos os métodos de criação de solicitações pendentes para abrir posições e definir ordens pendentes discutidos anteriormente e considerados em artigos anteriores, além disso, o código dos métodos é comentado em detalhes, portanto, nós os deixaremos para estudá-los por conta própria.

No arquivo Trading.mqh da classe principal do objeto de negociação da biblioteca, transferimos os métodos da seção privada da classe para a seção protegida:

private:
   CArrayInt            m_list_errors;                   // Error list
   bool                 m_is_trade_disable;              // Flag disabling trading
   bool                 m_use_sound;                     // The flag of using sounds of the object trading events
   ENUM_ERROR_HANDLING_BEHAVIOR m_err_handling_behavior; // Behavior when handling error
   
//--- Add the error code to the list
   bool                 AddErrorCodeToList(const int error_code);
//--- Return the symbol object by (1) position, (2) order ticket
   CSymbol             *GetSymbolObjByPosition(const ulong ticket,const string source_method);
   CSymbol             *GetSymbolObjByOrder(const ulong ticket,const string source_method);
//--- Return a symbol trading object by (1) position, (2) order ticket, (3) symbol name
   CTradeObj           *GetTradeObjByPosition(const ulong ticket,const string source_method);
   CTradeObj           *GetTradeObjByOrder(const ulong ticket,const string source_method);
   CTradeObj           *GetTradeObjBySymbol(const string symbol,const string source_method);
//--- Return an order object by ticket
   COrder              *GetOrderObjByTicket(const ulong ticket);


//--- Return the number of (1) all positions, (2) buy, (3) sell positions
   int                  PositionsTotalAll(void)          const;
   int                  PositionsTotalLong(void)         const;
   int                  PositionsTotalShort(void)        const;
//--- Return the number of (1) all pending orders, (2) buy, (3) sell pending orders
   int                  OrdersTotalAll(void)             const;
   int                  OrdersTotalLong(void)            const;
   int                  OrdersTotalShort(void)           const;
//--- Return the total volume of (1) buy, (2) sell positions
   double               PositionsTotalVolumeLong(void)   const;
   double               PositionsTotalVolumeShort(void)  const;
//--- Return the total volume of (1) buy, (2) sell orders
   double               OrdersTotalVolumeLong(void)      const;
   double               OrdersTotalVolumeShort(void)     const;
//--- Return the order direction by an operation type
   ENUM_ORDER_TYPE      DirectionByActionType(const ENUM_ACTION_TYPE action)  const;
//--- Check the presence of a (1) position, (2) order by ticket
   bool                 CheckPositionAvailablity(const ulong ticket,const string source_method);
   bool                 CheckOrderAvailablity(const ulong ticket,const string source_method);
//--- Set the desired sound for a trading object

Agora os métodos transferidos estão na seção protegida da classe:

//+------------------------------------------------------------------+
//| Trading class                                                    |
//+------------------------------------------------------------------+
class CTrading : public CBaseObj
  {
protected:
   CAccount            *m_account;                       // Pointer to the current account object
   CSymbolsCollection  *m_symbols;                       // Pointer to the symbol collection list
   CMarketCollection   *m_market;                        // Pointer to the list of the collection of market orders and positions
   CHistoryCollection  *m_history;                       // Pointer to the list of the collection of historical orders and deals
   CEventsCollection   *m_events;                        // Pointer to the event collection list
   CArrayObj            m_list_request;                  // List of pending requests
   uchar                m_total_try;                     // Number of trading attempts
   MqlTradeRequest      m_request;                       // Trade request structure
   ENUM_TRADE_REQUEST_ERR_FLAGS m_error_reason_flags;    // Flags of error source in a trading method
   
//--- Add the error code to the list
   bool                 AddErrorCodeToList(const int error_code);
//--- Look for the first free pending request ID
   int                  GetFreeID(void);
//--- Return the flag of a market order/position with a pending request ID
   bool                 IsPresentOrderByID(const uchar id);
//--- Return an order object by ticket
   COrder              *GetOrderObjByTicket(const ulong ticket);
//--- Return the symbol object by (1) position, (2) order ticket
   CSymbol             *GetSymbolObjByPosition(const ulong ticket,const string source_method);
   CSymbol             *GetSymbolObjByOrder(const ulong ticket,const string source_method);
//--- Return a symbol trading object by (1) position, (2) order ticket, (3) symbol name
   CTradeObj           *GetTradeObjByPosition(const ulong ticket,const string source_method);
   CTradeObj           *GetTradeObjByOrder(const ulong ticket,const string source_method);
   CTradeObj           *GetTradeObjBySymbol(const string symbol,const string source_method);
//--- Check the presence of a (1) position, (2) order by ticket
   bool                 CheckPositionAvailablity(const ulong ticket,const string source_method);
   bool                 CheckOrderAvailablity(const ulong ticket,const string source_method);
   
private:

Esses métodos são usados pela classe filho CTradingControl e devem estar na seção protegida.

À seção pública da classe do objeto principal da biblioteca CEngine adicionmos um método que retorne uma lista contendo todas as solicitações pendentes:

//--- Return (1) the list of references to resources, (2) resource object index by its description
   CArrayObj           *GetListResource(void)                                 { return this.m_resource.GetList();                               }
   int                  GetIndexResObjByDescription(const string file_name)   { return this.m_resource.GetIndexResObjByDescription(file_name);  }

//--- Return the list of pending requests
   CArrayObj           *GetListPendingRequests(void)                          { return this.m_trading.GetListRequests();                        }

//--- Set the following for the trading classes:
//--- (1) correct filling policy, (2) filling policy,
//--- (3) correct order expiration type, (4) order expiration type,
//--- (5) magic number, (6) comment, (7) slippage, (8) volume, (9) order expiration date,
//--- (10) the flag of asynchronous sending of a trading request, (11) logging level, (12) number of trading attempts

O método retorna a lista de solicitações pendentes chamando o método da classe de negociação GetListRequests().

Agora, com ajuda desse método, podemos obter uma lista completa contendo as solicitações pendentes existentes e classificar e pesquisar na lista usando os métodos de pesquisa e classificação que serão criados abaixo.

Na seção pública da classe, declaramos três métodos para criação de solicitações pendentes:
para fechamento completo de posição, para fechamento parcial de posição e para fechamento mediante posição oposta:

//--- Create a pending request (1) to open Buy and (2) Sell positions
   template<typename SL,typename TP> 
   int                  OpenBuyPending(const double volume,
                                       const string symbol,
                                       const ulong magic=ULONG_MAX,
                                       const SL sl=0,
                                       const TP tp=0,
                                       const uchar group_id1=0,
                                       const uchar group_id2=0,
                                       const string comment=NULL,
                                       const ulong deviation=ULONG_MAX,
                                       const ENUM_ORDER_TYPE_FILLING type_filling=WRONG_VALUE);
   template<typename SL,typename TP> 
   int                  OpenSellPending(const double volume,
                                       const string symbol,
                                       const ulong magic=ULONG_MAX,
                                       const SL sl=0,
                                       const TP tp=0,
                                       const uchar group_id1=0,
                                       const uchar group_id2=0,
                                       const string comment=NULL,
                                       const ulong deviation=ULONG_MAX,
                                       const ENUM_ORDER_TYPE_FILLING type_filling=WRONG_VALUE);
                                       
//--- Create a pending request for closing a position (1) fully, (2) partially, (3) by an opposite one
   int                  ClosePositionPending(const ulong ticket,const string comment=NULL,const ulong deviation=ULONG_MAX);
   int                  ClosePositionPartiallyPending(const ulong ticket,const double volume,const string comment=NULL,const ulong deviation=ULONG_MAX);
   int                  ClosePositionByPending(const ulong ticket,const ulong ticket_by);
                                    
//--- Create a pending request to place a (1) BuyLimit, (2) BuyStop and (3) BuyStopLimit order

Fora do corpo da classe, escrevemos sua implementação:

//+------------------------------------------------------------------+
//| Create a pending request for closing a position in full          |
//+------------------------------------------------------------------+
int CEngine::ClosePositionPending(const ulong ticket,const string comment=NULL,const ulong deviation=WRONG_VALUE)
  {
   return this.m_trading.CreatePReqClose(ticket,WRONG_VALUE,comment,deviation);
  }
//+------------------------------------------------------------------+
//| Create a pending request for closing a position partially        |
//+------------------------------------------------------------------+
int CEngine::ClosePositionPartiallyPending(const ulong ticket,const double volume,const string comment=NULL,const ulong deviation=WRONG_VALUE)
  {
   return this.m_trading.CreatePReqClose(ticket,volume,comment,deviation);
  }
//+--------------------------------------------------------------------+
//| Create a pending request for closing a position by an opposite one |
//+--------------------------------------------------------------------+
int CEngine::ClosePositionByPending(const ulong ticket,const ulong ticket_by)
  {
   return this.m_trading.CreatePReqCloseBy(ticket,ticket_by);
  }
//+------------------------------------------------------------------+

Os métodos simplesmente chamam os métodos correspondentes para criação de solicitação pendentes da classe CTradingControl.
Para criar uma solicitação pendente para fechar completamente uma posição, ao método CreatePReqClose() da classe de gerenciamento de negociação é transferido WRONG_VALUE como o valor do volume a ser fechado, e para fechamento parcial, o valor do volume fechado passado para o método como parâmetro de entrada.

Agora, criaremos métodos para pesquisar e classificar objetos-solicitações pendentes na lista de solicitações pendentes.
Ao arquivo \MQL5\Include\DoEasy\ Services\Select.mqh anexamos o objeto da solicitação pendente abstrata e declaramos os métodos para trabalhar com solicitações pendentes:

//+------------------------------------------------------------------+
//|                                                       Select.mqh |
//|                        Copyright 2019, MetaQuotes Software Corp. |
//|                             https://mql5.com/en/users/artmedia70 |
//+------------------------------------------------------------------+
#property copyright "Copyright 2019, MetaQuotes Software Corp."
#property link      "https://mql5.com/ru/users/artmedia70"
#property version   "1.00"
//+------------------------------------------------------------------+
//| Include files                                                    |
//+------------------------------------------------------------------+
#include <Arrays\ArrayObj.mqh>
#include "..\Objects\Orders\Order.mqh"
#include "..\Objects\Events\Event.mqh"
#include "..\Objects\Accounts\Account.mqh"
#include "..\Objects\Symbols\Symbol.mqh"
#include "..\Objects\PendRequest\PendRequest.mqh"
//+------------------------------------------------------------------+
//| Storage list                                                     |
//+------------------------------------------------------------------+
CArrayObj   ListStorage; // Storage object for storing sorted collection lists
//+------------------------------------------------------------------+
//| Class for sorting objects meeting the criterion                  |
//+------------------------------------------------------------------+
class CSelect
  {
private:
   //--- Method for comparing two values
   template<typename T>
   static bool       CompareValues(T value1,T value2,ENUM_COMPARER_TYPE mode);
public:
//+------------------------------------------------------------------+
//| Methods of working with orders                                   |
//+------------------------------------------------------------------+
   //--- Return the list of orders with one out of (1) integer, (2) real and (3) string properties meeting a specified criterion
   static CArrayObj *ByOrderProperty(CArrayObj *list_source,ENUM_ORDER_PROP_INTEGER property,long value,ENUM_COMPARER_TYPE mode);
   static CArrayObj *ByOrderProperty(CArrayObj *list_source,ENUM_ORDER_PROP_DOUBLE property,double value,ENUM_COMPARER_TYPE mode);
   static CArrayObj *ByOrderProperty(CArrayObj *list_source,ENUM_ORDER_PROP_STRING property,string value,ENUM_COMPARER_TYPE mode);
   //--- Return the order index with the maximum value of the order's (1) integer, (2) real and (3) string properties
   static int        FindOrderMax(CArrayObj *list_source,ENUM_ORDER_PROP_INTEGER property);
   static int        FindOrderMax(CArrayObj *list_source,ENUM_ORDER_PROP_DOUBLE property);
   static int        FindOrderMax(CArrayObj *list_source,ENUM_ORDER_PROP_STRING property);
   //--- Return the order index with the minimum value of the order's (1) integer, (2) real and (3) string properties
   static int        FindOrderMin(CArrayObj *list_source,ENUM_ORDER_PROP_INTEGER property);
   static int        FindOrderMin(CArrayObj *list_source,ENUM_ORDER_PROP_DOUBLE property);
   static int        FindOrderMin(CArrayObj *list_source,ENUM_ORDER_PROP_STRING property);
//+------------------------------------------------------------------+
//| Methods of working with events                                   |
//+------------------------------------------------------------------+
   //--- Return the list of events with one out of (1) integer, (2) real and (3) string properties meeting a specified criterion
   static CArrayObj *ByEventProperty(CArrayObj *list_source,ENUM_EVENT_PROP_INTEGER property,long value,ENUM_COMPARER_TYPE mode);
   static CArrayObj *ByEventProperty(CArrayObj *list_source,ENUM_EVENT_PROP_DOUBLE property,double value,ENUM_COMPARER_TYPE mode);
   static CArrayObj *ByEventProperty(CArrayObj *list_source,ENUM_EVENT_PROP_STRING property,string value,ENUM_COMPARER_TYPE mode);
   //--- Return the event index with the maximum value of the event's (1) integer, (2) real and (3) string properties
   static int        FindEventMax(CArrayObj *list_source,ENUM_EVENT_PROP_INTEGER property);
   static int        FindEventMax(CArrayObj *list_source,ENUM_EVENT_PROP_DOUBLE property);
   static int        FindEventMax(CArrayObj *list_source,ENUM_EVENT_PROP_STRING property);
   //--- Return the event index with the minimum value of the event's (1) integer, (2) real and (3) string properties
   static int        FindEventMin(CArrayObj *list_source,ENUM_EVENT_PROP_INTEGER property);
   static int        FindEventMin(CArrayObj *list_source,ENUM_EVENT_PROP_DOUBLE property);
   static int        FindEventMin(CArrayObj *list_source,ENUM_EVENT_PROP_STRING property);
//+------------------------------------------------------------------+
//| Methods of working with accounts                                 |
//+------------------------------------------------------------------+
   //--- Return the list of accounts with one out of (1) integer, (2) real and (3) string properties meeting a specified criterion
   static CArrayObj *ByAccountProperty(CArrayObj *list_source,ENUM_ACCOUNT_PROP_INTEGER property,long value,ENUM_COMPARER_TYPE mode);
   static CArrayObj *ByAccountProperty(CArrayObj *list_source,ENUM_ACCOUNT_PROP_DOUBLE property,double value,ENUM_COMPARER_TYPE mode);
   static CArrayObj *ByAccountProperty(CArrayObj *list_source,ENUM_ACCOUNT_PROP_STRING property,string value,ENUM_COMPARER_TYPE mode);
   //--- Return the event index with the maximum value of the event's (1) integer, (2) real and (3) string properties
   static int        FindAccountMax(CArrayObj *list_source,ENUM_ACCOUNT_PROP_INTEGER property);
   static int        FindAccountMax(CArrayObj *list_source,ENUM_ACCOUNT_PROP_DOUBLE property);
   static int        FindAccountMax(CArrayObj *list_source,ENUM_ACCOUNT_PROP_STRING property);
   //--- Return the event index with the minimum value of the event's (1) integer, (2) real and (3) string properties
   static int        FindAccountMin(CArrayObj *list_source,ENUM_ACCOUNT_PROP_INTEGER property);
   static int        FindAccountMin(CArrayObj *list_source,ENUM_ACCOUNT_PROP_DOUBLE property);
   static int        FindAccountMin(CArrayObj *list_source,ENUM_ACCOUNT_PROP_STRING property);
//+------------------------------------------------------------------+
//| Methods of working with symbols                                  |
//+------------------------------------------------------------------+
   //--- Return the list of symbols with one out of (1) integer, (2) real and (3) string properties meeting a specified criterion
   static CArrayObj *BySymbolProperty(CArrayObj *list_source,ENUM_SYMBOL_PROP_INTEGER property,long value,ENUM_COMPARER_TYPE mode);
   static CArrayObj *BySymbolProperty(CArrayObj *list_source,ENUM_SYMBOL_PROP_DOUBLE property,double value,ENUM_COMPARER_TYPE mode);
   static CArrayObj *BySymbolProperty(CArrayObj *list_source,ENUM_SYMBOL_PROP_STRING property,string value,ENUM_COMPARER_TYPE mode);
   //--- Return the symbol index with the maximum value of the order's (1) integer, (2) real and (3) string properties
   static int        FindSymbolMax(CArrayObj *list_source,ENUM_SYMBOL_PROP_INTEGER property);
   static int        FindSymbolMax(CArrayObj *list_source,ENUM_SYMBOL_PROP_DOUBLE property);
   static int        FindSymbolMax(CArrayObj *list_source,ENUM_SYMBOL_PROP_STRING property);
   //--- Return the symbol index with the minimum value of the order's (1) integer, (2) real and (3) string properties
   static int        FindSymbolMin(CArrayObj *list_source,ENUM_SYMBOL_PROP_INTEGER property);
   static int        FindSymbolMin(CArrayObj *list_source,ENUM_SYMBOL_PROP_DOUBLE property);
   static int        FindSymbolMin(CArrayObj *list_source,ENUM_SYMBOL_PROP_STRING property);
//+-------------------------------------------------------------------+
//| Methods of working with pending requests                          |
//+-------------------------------------------------------------------+
   //--- Return the list of pending requests with one out of (1) integer, (2) real and (3) string properties meeting a specified criterion
   static CArrayObj *ByPendReqProperty(CArrayObj *list_source,ENUM_PEND_REQ_PROP_INTEGER property,long value,ENUM_COMPARER_TYPE mode);
   static CArrayObj *ByPendReqProperty(CArrayObj *list_source,ENUM_PEND_REQ_PROP_DOUBLE property,double value,ENUM_COMPARER_TYPE mode);
   static CArrayObj *ByPendReqProperty(CArrayObj *list_source,ENUM_PEND_REQ_PROP_STRING property,string value,ENUM_COMPARER_TYPE mode);
   //--- Return the pending request index with the maximum value of the order's (1) integer, (2) real and (3) string properties
   static int        FindPendReqMax(CArrayObj *list_source,ENUM_PEND_REQ_PROP_INTEGER property);
   static int        FindPendReqMax(CArrayObj *list_source,ENUM_PEND_REQ_PROP_DOUBLE property);
   static int        FindPendReqMax(CArrayObj *list_source,ENUM_PEND_REQ_PROP_STRING property);
   //--- Return the pending request index with the minimum value of the order's (1) integer, (2) real and (3) string properties
   static int        FindPendReqMin(CArrayObj *list_source,ENUM_PEND_REQ_PROP_INTEGER property);
   static int        FindPendReqMin(CArrayObj *list_source,ENUM_PEND_REQ_PROP_DOUBLE property);
   static int        FindPendReqMin(CArrayObj *list_source,ENUM_PEND_REQ_PROP_STRING property);
//---
  };
//+------------------------------------------------------------------+

Fora do corpo da classe, escrevemos uma implementação de métodos para classificar e pesquisar na lista de solicitações pendentes:

//+------------------------------------------------------------------+
//| Methods of working with lists of pending trading requests        |
//+------------------------------------------------------------------+
//+------------------------------------------------------------------+
//| Return the list of requests with one integer                     |
//| property meeting the specified criterion                         |
//+------------------------------------------------------------------+
CArrayObj *CSelect::ByPendReqProperty(CArrayObj *list_source,ENUM_PEND_REQ_PROP_INTEGER property,long value,ENUM_COMPARER_TYPE mode)
  {
   if(list_source==NULL) return NULL;
   CArrayObj *list=new CArrayObj();
   if(list==NULL) return NULL;
   list.FreeMode(false);
   ListStorage.Add(list);
   int total=list_source.Total();
   for(int i=0; i<total; i++)
     {
      CPendRequest *obj=list_source.At(i);
      if(!obj.SupportProperty(property)) continue;
      long obj_prop=obj.GetProperty(property);
      if(CompareValues(obj_prop,value,mode)) list.Add(obj);
     }
   return list;
  }
//+------------------------------------------------------------------+
//| Return the list of requests with one real                        |
//| property meeting the specified criterion                         |
//+------------------------------------------------------------------+
CArrayObj *CSelect::ByPendReqProperty(CArrayObj *list_source,ENUM_PEND_REQ_PROP_DOUBLE property,double value,ENUM_COMPARER_TYPE mode)
  {
   if(list_source==NULL) return NULL;
   CArrayObj *list=new CArrayObj();
   if(list==NULL) return NULL;
   list.FreeMode(false);
   ListStorage.Add(list);
   for(int i=0; i<list_source.Total(); i++)
     {
      CPendRequest *obj=list_source.At(i);
      if(!obj.SupportProperty(property)) continue;
      double obj_prop=obj.GetProperty(property);
      if(CompareValues(obj_prop,value,mode)) list.Add(obj);
     }
   return list;
  }
//+------------------------------------------------------------------+
//| Return the list of requests with one string                      |
//| property meeting the specified criterion                         |
//+------------------------------------------------------------------+
CArrayObj *CSelect::ByPendReqProperty(CArrayObj *list_source,ENUM_PEND_REQ_PROP_STRING property,string value,ENUM_COMPARER_TYPE mode)
  {
   if(list_source==NULL) return NULL;
   CArrayObj *list=new CArrayObj();
   if(list==NULL) return NULL;
   list.FreeMode(false);
   ListStorage.Add(list);
   for(int i=0; i<list_source.Total(); i++)
     {
      CPendRequest *obj=list_source.At(i);
      if(!obj.SupportProperty(property)) continue;
      string obj_prop=obj.GetProperty(property);
      if(CompareValues(obj_prop,value,mode)) list.Add(obj);
     }
   return list;
  }
//+------------------------------------------------------------------+
//| Return the listed request index                                  |
//| with the maximum integer property value                          |
//+------------------------------------------------------------------+
int CSelect::FindPendReqMax(CArrayObj *list_source,ENUM_PEND_REQ_PROP_INTEGER property)
  {
   if(list_source==NULL) return WRONG_VALUE;
   int index=0;
   CPendRequest *max_obj=NULL;
   int total=list_source.Total();
   if(total==0) return WRONG_VALUE;
   for(int i=1; i<total; i++)
     {
      CPendRequest *obj=list_source.At(i);
      long obj1_prop=obj.GetProperty(property);
      max_obj=list_source.At(index);
      long obj2_prop=max_obj.GetProperty(property);
      if(CompareValues(obj1_prop,obj2_prop,MORE)) index=i;
     }
   return index;
  }
//+------------------------------------------------------------------+
//| Return the listed request index                                  |
//| with the maximum real property value                             |
//+------------------------------------------------------------------+
int CSelect::FindPendReqMax(CArrayObj *list_source,ENUM_PEND_REQ_PROP_DOUBLE property)
  {
   if(list_source==NULL) return WRONG_VALUE;
   int index=0;
   CPendRequest *max_obj=NULL;
   int total=list_source.Total();
   if(total==0) return WRONG_VALUE;
   for(int i=1; i<total; i++)
     {
      CPendRequest *obj=list_source.At(i);
      double obj1_prop=obj.GetProperty(property);
      max_obj=list_source.At(index);
      double obj2_prop=max_obj.GetProperty(property);
      if(CompareValues(obj1_prop,obj2_prop,MORE)) index=i;
     }
   return index;
  }
//+------------------------------------------------------------------+
//| Return the listed request index                                  |
//| with the maximum string property value                           |
//+------------------------------------------------------------------+
int CSelect::FindPendReqMax(CArrayObj *list_source,ENUM_PEND_REQ_PROP_STRING property)
  {
   if(list_source==NULL) return WRONG_VALUE;
   int index=0;
   CPendRequest *max_obj=NULL;
   int total=list_source.Total();
   if(total==0) return WRONG_VALUE;
   for(int i=1; i<total; i++)
     {
      CPendRequest *obj=list_source.At(i);
      string obj1_prop=obj.GetProperty(property);
      max_obj=list_source.At(index);
      string obj2_prop=max_obj.GetProperty(property);
      if(CompareValues(obj1_prop,obj2_prop,MORE)) index=i;
     }
   return index;
  }
//+------------------------------------------------------------------+
//| Return the listed request index                                  |
//| with the minimum integer property value                          |
//+------------------------------------------------------------------+
int CSelect::FindPendReqMin(CArrayObj* list_source,ENUM_PEND_REQ_PROP_INTEGER property)
  {
   int index=0;
   CPendRequest *min_obj=NULL;
   int total=list_source.Total();
   if(total==0) return WRONG_VALUE;
   for(int i=1; i<total; i++)
     {
      CPendRequest *obj=list_source.At(i);
      long obj1_prop=obj.GetProperty(property);
      min_obj=list_source.At(index);
      long obj2_prop=min_obj.GetProperty(property);
      if(CompareValues(obj1_prop,obj2_prop,LESS)) index=i;
     }
   return index;
  }
//+------------------------------------------------------------------+
//| Return the listed request index                                  |
//| with the minimum real property value                             |
//+------------------------------------------------------------------+
int CSelect::FindPendReqMin(CArrayObj* list_source,ENUM_PEND_REQ_PROP_DOUBLE property)
  {
   int index=0;
   CPendRequest *min_obj=NULL;
   int total=list_source.Total();
   if(total== 0) return WRONG_VALUE;
   for(int i=1; i<total; i++)
     {
      CPendRequest *obj=list_source.At(i);
      double obj1_prop=obj.GetProperty(property);
      min_obj=list_source.At(index);
      double obj2_prop=min_obj.GetProperty(property);
      if(CompareValues(obj1_prop,obj2_prop,LESS)) index=i;
     }
   return index;
  }
//+------------------------------------------------------------------+
//| Return the listed request index                                  |
//| with the minimum string property value                           |
//+------------------------------------------------------------------+
int CSelect::FindPendReqMin(CArrayObj* list_source,ENUM_PEND_REQ_PROP_STRING property)
  {
   int index=0;
   CPendRequest *min_obj=NULL;
   int total=list_source.Total();
   if(total==0) return WRONG_VALUE;
   for(int i=1; i<total; i++)
     {
      CPendRequest *obj=list_source.At(i);
      string obj1_prop=obj.GetProperty(property);
      min_obj=list_source.At(index);
      string obj2_prop=min_obj.GetProperty(property);
      if(CompareValues(obj1_prop,obj2_prop,LESS)) index=i;
     }
   return index;
  }
//+------------------------------------------------------------------+

No terceiro artigo que fala sobre pesquisa por meio de coleções de bibliotecas, abordamos bem o funcionamento desses métodos.
Aqui não há diferenças na lógica de operação desses métodos, exceto que esses métodos de pesquisa e classificação funcionam com objetos e dados de solicitações pendentes da classe CPendRequest.

Essas são todas as alterações nas classes da biblioteca para gerar o fechamento de posições por condições usando solicitações de negociação pendentes.

Teste

Para testar o fechamento de posições segundo condições, pegamos o EA do artigo anterior e o salvamos na nova pasta \MQL5\Experts\TestDoEasy\Part33\ usando o nome novo TestDoEasyPart33.mq5.

No bloco de variáveis globais do EA, mudei os nomes das variáveis que armazenam os sinalizadores de estado dos botões de ativação dos modos de negociação com ajuda de solicitações pendentes:

//--- global variables
CEngine        engine;
SDataButt      butt_data[TOTAL_BUTT];
string         prefix;
double         lot;
double         withdrawal=(InpWithdrawal<0.1 ? 0.1 : InpWithdrawal);
ushort         magic_number;
uint           stoploss;
uint           takeprofit;
uint           distance_pending;
uint           distance_stoplimit;
uint           distance_pending_request;
uint           bars_delay_pending_request;
uint           slippage;
bool           trailing_on;
bool           pending_buy;
bool           pending_buy_limit;
bool           pending_buy_stop;
bool           pending_buy_stoplimit;
bool           pending_close_buy;
bool           pending_close_buy2;
bool           pending_close_buy_by_sell;
bool           pending_sell;
bool           pending_sell_limit;
bool           pending_sell_stop;
bool           pending_sell_stoplimit;
bool           pending_close_sell;
bool           pending_close_sell2;
bool           pending_close_sell_by_buy;
double         trailing_stop;
double         trailing_step;
uint           trailing_start;
uint           stoploss_to_modify;
uint           takeprofit_to_modify;
int            used_symbols_mode;
string         used_symbols;
string         array_used_symbols[];
bool           testing;
uchar          group1;
uchar          group2;
//+------------------------------------------------------------------+

Agora essas variáveis têm nomes mais legíveis:

//--- global variables
CEngine        engine;
SDataButt      butt_data[TOTAL_BUTT];
string         prefix;
double         lot;
double         withdrawal=(InpWithdrawal<0.1 ? 0.1 : InpWithdrawal);
ushort         magic_number;
uint           stoploss;
uint           takeprofit;
uint           distance_pending;
uint           distance_stoplimit;
uint           distance_pending_request;
uint           bars_delay_pending_request;
uint           slippage;
bool           trailing_on;
bool           pressed_pending_buy;
bool           pressed_pending_buy_limit;
bool           pressed_pending_buy_stop;
bool           pressed_pending_buy_stoplimit;
bool           pressed_pending_close_buy;
bool           pressed_pending_close_buy2;
bool           pressed_pending_close_buy_by_sell;
bool           pressed_pending_sell;
bool           pressed_pending_sell_limit;
bool           pressed_pending_sell_stop;
bool           pressed_pending_sell_stoplimit;
bool           pressed_pending_close_sell;
bool           pressed_pending_close_sell2;
bool           pressed_pending_close_sell_by_buy;
double         trailing_stop;
double         trailing_step;
uint           trailing_start;
uint           stoploss_to_modify;
uint           takeprofit_to_modify;
int            used_symbols_mode;
string         used_symbols;
string         array_used_symbols[];
bool           testing;
uchar          group1;
uchar          group2;
//+------------------------------------------------------------------+

Com Ctrl+H foi feita uma pesquisa no texto para encontrar "pending_" e substituir essa entrada por "pressed_pending_", a fim de todas essas variáveis serem renomeadas em todo o código do EA em que as encontramos.

Na função PressButtonEvents() para processar pressionamentos de botão no EA existem blocos de código do mesmo tipo para definir condições de ativação para objetos recém-criados de solicitações de negociação pendentes:

   //--- If the button is pressed
   if(ButtonState(button_name))
     {
      //--- If the BUTT_BUY button is pressed: Open Buy position
      if(button==EnumToString(BUTT_BUY))
        {
         //--- If the pending request creation buttons are not pressed, open Buy 
         if(!pending_buy)
            engine.OpenBuy(lot,Symbol(),magic,stoploss,takeprofit);   // No comment - the default comment is to be set
         //--- Otherwise, create a pending request for opening a Buy position
         else
           {
            int id=engine.OpenBuyPending(lot,Symbol(),magic,stoploss,takeprofit);
            if(id>0)
              {
               //--- If the price criterion is selected
               if(ButtonState(prefix+EnumToString(BUTT_BUY)+"_PRICE"))
                 {
                  double ask=SymbolInfoDouble(NULL,SYMBOL_ASK);
                  double control_value=NormalizeDouble(ask-distance_pending_request*SymbolInfoDouble(NULL,SYMBOL_POINT),(int)SymbolInfoInteger(NULL,SYMBOL_DIGITS));
                  engine.SetNewActivationProperties((uchar)id,PEND_REQ_ACTIVATION_SOURCE_SYMBOL,PEND_REQ_ACTIVATE_BY_SYMBOL_ASK,control_value,EQUAL_OR_LESS,ask);
                 }
               //--- If the time criterion is selected
               if(ButtonState(prefix+EnumToString(BUTT_BUY)+"_TIME"))
                 {
                  ulong control_time=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
                  engine.SetNewActivationProperties((uchar)id,PEND_REQ_ACTIVATION_SOURCE_SYMBOL,PEND_REQ_ACTIVATE_BY_SYMBOL_TIME,control_time,EQUAL_OR_MORE,TimeCurrent());
                 }
               CPendRequest *req_obj=engine.GetPendRequestByID((uchar)id);
               if(req_obj==NULL)
                  return;
               if(engine.TradingGetLogLevel(Symbol())>LOG_LEVEL_NO_MSG)
                 {
                  ::Print(CMessage::Text(MSG_LIB_TEXT_PEND_REQUEST_ADD_CRITERIONS)," #",req_obj.ID(),":");
                  req_obj.PrintActivations();
                 }
              }
           }
        }
      //--- If the BUTT_BUY_LIMIT button is pressed: Place BuyLimit
      else if(button==EnumToString(BUTT_BUY_LIMIT))
        {

Para reduzir a quantidade de código escrito, todos esses blocos de código recorrentes devem ser colocados numa função separada que utilizará os parâmetros necessários para definir as condições de ativação dos objetos-solicitações pendentes.

Escrevemos a função a seguir:

//+------------------------------------------------------------------+
//| Set pending request activation conditions                        |
//+------------------------------------------------------------------+
void SetPReqCriterion(const uchar id,const double price_activation,const ulong time_activation,ENUM_BUTTONS button,ENUM_COMPARER_TYPE comp_type,const double price_curr,const datetime time_curr)
  {
   double point=SymbolInfoDouble(NULL,SYMBOL_POINT);
   int    digits=(int)SymbolInfoInteger(NULL,SYMBOL_DIGITS);
//--- If the price criterion is selected
   if(ButtonState(prefix+EnumToString(button)+"_PRICE"))
     {
      //--- set the pending request activation price
      engine.SetNewActivationProperties((uchar)id,PEND_REQ_ACTIVATION_SOURCE_SYMBOL,PEND_REQ_ACTIVATE_BY_SYMBOL_BID,price_activation,comp_type,price_curr);
     }
//--- If the time criterion is selected
   if(ButtonState(prefix+EnumToString(button)+"_TIME"))
     {
      //--- set the pending request activation time
      engine.SetNewActivationProperties((uchar)id,PEND_REQ_ACTIVATION_SOURCE_SYMBOL,PEND_REQ_ACTIVATE_BY_SYMBOL_TIME,time_activation,EQUAL_OR_MORE,time_curr);
     }
//--- Get a newly created pending request by ID and display the message about adding the conditions to the journal
   CPendRequest *req_obj=engine.GetPendRequestByID((uchar)id);
   if(req_obj==NULL)
      return;
   if(engine.TradingGetLogLevel(Symbol())>LOG_LEVEL_NO_MSG)
     {
      ::Print(CMessage::Text(MSG_LIB_TEXT_PEND_REQUEST_ADD_CRITERIONS),", ID #",req_obj.ID(),":");
      req_obj.PrintActivations();
     }
  }
//+------------------------------------------------------------------+

À função são transferidos o identificador do novo objeto-solicitação pendente, o preço e a hora de ativação da solicitação, a constante de nome do botão pressionado, o tipo de comparação e o preço e a hora atuais.
Além disso, dependendo do nome do botão pressionado, no objeto-solicitação são definidas suas condições de ativação e é exibida uma mensagem no log sobre a adição de condições de ativação à solicitação pendente.

Agora na função PressButtonEvents() substituímos os blocos de código do mesmo tipo, mencionados acima, pela chamada de nova função para definir as condições de ativação das solicitações pendentes, e, ao mesmo tempo, adicionamos o pressionamento dos botões de fechamento de posições:

//+------------------------------------------------------------------+
//| Handle pressing the buttons                                      |
//+------------------------------------------------------------------+
void PressButtonEvents(const string button_name)
  {
   bool comp_magic=true;   // Temporary variable selecting the composite magic number with random group IDs
   string comment="";
   double point=SymbolInfoDouble(NULL,SYMBOL_POINT);
   int    digits=(int)SymbolInfoInteger(NULL,SYMBOL_DIGITS);
   //--- Convert button name into its string ID
   string button=StringSubstr(button_name,StringLen(prefix));
   //--- Random group 1 and 2 numbers within the range of 0 - 15
   group1=(uchar)Rand();
   group2=(uchar)Rand();
   uint magic=(comp_magic ? engine.SetCompositeMagicNumber(magic_number,group1,group2) : magic_number);
   //--- If the button is pressed
   if(ButtonState(button_name))
     {
      //--- If the BUTT_BUY button is pressed: Open Buy position
      if(button==EnumToString(BUTT_BUY))
        {
         //--- If the pending request creation buttons are not pressed, open Buy 
         if(!pressed_pending_buy)
            engine.OpenBuy(lot,Symbol(),magic,stoploss,takeprofit);   // No comment - the default comment is to be set
         //--- Otherwise, create a pending request for opening a Buy position
         else
           {
            int id=engine.OpenBuyPending(lot,Symbol(),magic,stoploss,takeprofit);
            if(id>0)
              {
               //--- set the pending request activation price and time, as well as set activation parameters
               double ask=SymbolInfoDouble(NULL,SYMBOL_ASK);
               double price_activation=NormalizeDouble(ask-distance_pending_request*point,digits);
               ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
               SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_BUY,EQUAL_OR_LESS,ask,TimeCurrent());
              }
           }
        }
      //--- If the BUTT_BUY_LIMIT button is pressed: Place BuyLimit
      else if(button==EnumToString(BUTT_BUY_LIMIT))
        {
         //--- If the pending request creation buttons are not pressed, set BuyLimit
         if(!pressed_pending_buy_limit)
            engine.PlaceBuyLimit(lot,Symbol(),distance_pending,stoploss,takeprofit,magic,TextByLanguage("Отложенный BuyLimit","Pending BuyLimit order"));
         //--- Otherwise, create a pending request to place a BuyLimit order with the placement distance
         //--- and set the conditions depending on active buttons
         else
           {
            int id=engine.PlaceBuyLimitPending(lot,Symbol(),distance_pending,stoploss,takeprofit,magic);
            if(id>0)
              {
               //--- set the pending request activation price and time, as well as set activation parameters
               double ask=SymbolInfoDouble(NULL,SYMBOL_ASK);
               double price_activation=NormalizeDouble(ask-distance_pending_request*point,digits);
               ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
               SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_BUY_LIMIT,EQUAL_OR_LESS,ask,TimeCurrent());
              }
           }
        }
      //--- If the BUTT_BUY_STOP button is pressed: Set BuyStop
      else if(button==EnumToString(BUTT_BUY_STOP))
        {
         //--- If the pending request creation buttons are not pressed, set BuyStop
         if(!pressed_pending_buy_stop)
            engine.PlaceBuyStop(lot,Symbol(),distance_pending,stoploss,takeprofit,magic,TextByLanguage("Отложенный BuyStop","Pending BuyStop order"));
         //--- Otherwise, create a pending request to place a BuyStop order with the placement distance
         //--- and set the conditions depending on active buttons
         else
           {
            int id=engine.PlaceBuyStopPending(lot,Symbol(),distance_pending,stoploss,takeprofit,magic);
            if(id>0)
              {
               //--- set the pending request activation price and time, as well as set activation parameters
               double ask=SymbolInfoDouble(NULL,SYMBOL_ASK);
               double price_activation=NormalizeDouble(ask-distance_pending_request*point,digits);
               ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
               SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_BUY_STOP,EQUAL_OR_LESS,ask,TimeCurrent());
              }
           }
        }
      //--- If the BUTT_BUY_STOP_LIMIT button is pressed: Set BuyStopLimit
      else if(button==EnumToString(BUTT_BUY_STOP_LIMIT))
        {
         //--- If the pending request creation buttons are not pressed, set BuyStopLimit
         if(!pressed_pending_buy_stoplimit)
            engine.PlaceBuyStopLimit(lot,Symbol(),distance_pending,distance_stoplimit,stoploss,takeprofit,magic,TextByLanguage("Отложенный BuyStopLimit","Pending order BuyStopLimit"));
         //--- Otherwise, create a pending request to place a BuyStopLimit order with the placement distances
         //--- and set the conditions depending on active buttons
         else
           {
            int id=engine.PlaceBuyStopLimitPending(lot,Symbol(),distance_pending,distance_stoplimit,stoploss,takeprofit,magic);
            if(id>0)
              {
               //--- set the pending request activation price and time, as well as set activation parameters
               double ask=SymbolInfoDouble(NULL,SYMBOL_ASK);
               double price_activation=NormalizeDouble(ask-distance_pending_request*point,digits);
               ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
               SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_BUY_STOP_LIMIT,EQUAL_OR_LESS,ask,TimeCurrent());
              }
           }
        }
      //--- If the BUTT_SELL button is pressed: Open Sell position
      else if(button==EnumToString(BUTT_SELL))
        {
         //--- If the pending request creation buttons are not pressed, open Sell
         if(!pressed_pending_sell)
            engine.OpenSell(lot,Symbol(),magic,stoploss,takeprofit);  // No comment - the default comment is to be set
         //--- Otherwise, create a pending request for opening a Sell position
         else
           {
            int id=engine.OpenSellPending(lot,Symbol(),magic,stoploss,takeprofit);
            if(id>0)
              {
               //--- set the pending request activation price and time, as well as set activation parameters
               double bid=SymbolInfoDouble(NULL,SYMBOL_BID);
               double price_activation=NormalizeDouble(bid+distance_pending_request*point,digits);
               ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
               SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_SELL,EQUAL_OR_MORE,bid,TimeCurrent());
              }
           }
        }
      //--- If the BUTT_SELL_LIMIT button is pressed: Set SellLimit
      else if(button==EnumToString(BUTT_SELL_LIMIT))
        {
         //--- If the pending request creation buttons are not pressed, set SellLimit
         if(!pressed_pending_sell_limit)
            engine.PlaceSellLimit(lot,Symbol(),distance_pending,stoploss,takeprofit,magic,TextByLanguage("Отложенный SellLimit","Pending SellLimit order"));
         //--- Otherwise, create a pending request to place a SellLimit order with the placement distance
         //--- and set the conditions depending on active buttons
         else
           {
            int id=engine.PlaceSellLimitPending(lot,Symbol(),distance_pending,stoploss,takeprofit,magic);
            if(id>0)
              {
               //--- set the pending request activation price and time, as well as set activation parameters
               double bid=SymbolInfoDouble(NULL,SYMBOL_BID);
               double price_activation=NormalizeDouble(bid+distance_pending_request*point,digits);
               ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
               SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_SELL_LIMIT,EQUAL_OR_MORE,bid,TimeCurrent());
              }
           }
        }
      //--- If the BUTT_SELL_STOP button is pressed: Set SellStop
      else if(button==EnumToString(BUTT_SELL_STOP))
        {
         //--- If the pending request creation buttons are not pressed, set SellStop
         if(!pressed_pending_sell_stop)
            engine.PlaceSellStop(lot,Symbol(),distance_pending,stoploss,takeprofit,magic,TextByLanguage("Отложенный SellStop","Pending SellStop order"));
         //--- Otherwise, create a pending request to place a SellStop order with the placement distance
         //--- and set the conditions depending on active buttons
         else
           {
            int id=engine.PlaceSellStopPending(lot,Symbol(),distance_pending,stoploss,takeprofit,magic);
            if(id>0)
              {
               //--- set the pending request activation price and time, as well as set activation parameters
               double bid=SymbolInfoDouble(NULL,SYMBOL_BID);
               double price_activation=NormalizeDouble(bid+distance_pending_request*point,digits);
               ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
               SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_SELL_STOP,EQUAL_OR_MORE,bid,TimeCurrent());
              }
           }
        }
      //--- If the BUTT_SELL_STOP_LIMIT button is pressed: Set SellStopLimit
      else if(button==EnumToString(BUTT_SELL_STOP_LIMIT))
        {
         //--- If the pending request creation buttons are not pressed, set SellStopLimit
         if(!pressed_pending_sell_stoplimit)
            engine.PlaceSellStopLimit(lot,Symbol(),distance_pending,distance_stoplimit,stoploss,takeprofit,magic,TextByLanguage("Отложенный SellStopLimit","Pending SellStopLimit order"));
         //--- Otherwise, create a pending request to place a SellStopLimit order with the placement distances
         //--- and set the conditions depending on active buttons
         else
           {
            int id=engine.PlaceSellStopLimitPending(lot,Symbol(),distance_pending,distance_stoplimit,stoploss,takeprofit,magic);
            if(id>0)
              {
               //--- set the pending request activation price and time, as well as set activation parameters
               double bid=SymbolInfoDouble(NULL,SYMBOL_BID);
               double price_activation=NormalizeDouble(bid+distance_pending_request*point,digits);
               ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
               SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_SELL_STOP_LIMIT,EQUAL_OR_MORE,bid,TimeCurrent());
              }
           }
        }
      //--- If the BUTT_CLOSE_BUY button is pressed: Close Buy with the maximum profit
      else if(button==EnumToString(BUTT_CLOSE_BUY))
        {
         //--- Get the list of all open positions
         CArrayObj* list=engine.GetListMarketPosition();
         //--- Select only Buy positions from the list and for the current symbol only
         list=CSelect::ByOrderProperty(list,ORDER_PROP_SYMBOL,Symbol(),EQUAL);
         list=CSelect::ByOrderProperty(list,ORDER_PROP_TYPE,POSITION_TYPE_BUY,EQUAL);
         //--- Sort the list by profit considering commission and swap
         list.Sort(SORT_BY_ORDER_PROFIT_FULL);
         //--- Get the index of the Buy position with the maximum profit
         int index=CSelect::FindOrderMax(list,ORDER_PROP_PROFIT_FULL);
         if(index>WRONG_VALUE)
           {
            //--- Get the Buy position object and close a position by ticket
            COrder* position=list.At(index);
            if(position!=NULL)
              {
               //--- If the pending request creation buttons are not pressed, close a position
               if(!pressed_pending_close_buy)
                  engine.ClosePosition((ulong)position.Ticket());
               //--- Otherwise, create a pending request for closing a position by ticket
               //--- and set the conditions depending on active buttons
               else
                 {
                  int id=engine.ClosePositionPending(position.Ticket());
                  if(id>0)
                    {
                     //--- set the pending request activation price and time, as well as set activation parameters
                     double bid=SymbolInfoDouble(NULL,SYMBOL_BID);
                     double price_activation=NormalizeDouble(bid+distance_pending_request*point,digits);
                     ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
                     SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_CLOSE_BUY,EQUAL_OR_MORE,bid,TimeCurrent());
                    }
                 }
              }
           }
        }
      //--- If the BUTT_CLOSE_BUY2 button is pressed: Close the half of the Buy with the maximum profit
      else if(button==EnumToString(BUTT_CLOSE_BUY2))
        {
         //--- Get the list of all open positions
         CArrayObj* list=engine.GetListMarketPosition();
         //--- Select only Buy positions from the list and for the current symbol only
         list=CSelect::ByOrderProperty(list,ORDER_PROP_SYMBOL,Symbol(),EQUAL);
         list=CSelect::ByOrderProperty(list,ORDER_PROP_TYPE,POSITION_TYPE_BUY,EQUAL);
         //--- Sort the list by profit considering commission and swap
         list.Sort(SORT_BY_ORDER_PROFIT_FULL);
         //--- Get the index of the Buy position with the maximum profit
         int index=CSelect::FindOrderMax(list,ORDER_PROP_PROFIT_FULL);
         if(index>WRONG_VALUE)
           {
            //--- Get the Buy position object and close a position by ticket
            COrder* position=list.At(index);
            if(position!=NULL)
              {
               //--- If the pending request creation buttons are not pressed, close a position by ticket
               if(!pressed_pending_close_buy2)
                  engine.ClosePositionPartially((ulong)position.Ticket(),position.Volume()/2.0);
               //--- Otherwise, create a pending request for closing a position partially by ticket
               //--- and set the conditions depending on active buttons
               else
                 {
                  int id=engine.ClosePositionPartiallyPending(position.Ticket(),position.Volume()/2.0);
                  if(id>0)
                    {
                     //--- set the pending request activation price and time, as well as set activation parameters
                     double bid=SymbolInfoDouble(NULL,SYMBOL_BID);
                     double price_activation=NormalizeDouble(bid+distance_pending_request*point,digits);
                     ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
                     SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_CLOSE_BUY2,EQUAL_OR_MORE,bid,TimeCurrent());
                    }
                 }
              }
           }
        }
      //--- If the BUTT_CLOSE_BUY_BY_SELL button is pressed: Close Buy with the maximum profit by the opposite Sell with the maximum profit
      else if(button==EnumToString(BUTT_CLOSE_BUY_BY_SELL))
        {
         //--- In case of a hedging account
         if(engine.IsHedge())
           {
            CArrayObj *list_buy=NULL, *list_sell=NULL;
            //--- Get the list of all open positions
            CArrayObj* list=engine.GetListMarketPosition();
            if(list==NULL)
               return;
            //--- Select only current symbol positions from the list
            list=CSelect::ByOrderProperty(list,ORDER_PROP_SYMBOL,Symbol(),EQUAL);
            
            //--- Select only Buy positions from the list
            list_buy=CSelect::ByOrderProperty(list,ORDER_PROP_TYPE,POSITION_TYPE_BUY,EQUAL);
            if(list_buy==NULL)
               return;
            //--- Sort the list by profit considering commission and swap
            list_buy.Sort(SORT_BY_ORDER_PROFIT_FULL);
            //--- Get the index of the Buy position with the maximum profit
            int index_buy=CSelect::FindOrderMax(list_buy,ORDER_PROP_PROFIT_FULL);
            
            //--- Select only Sell positions from the list
            list_sell=CSelect::ByOrderProperty(list,ORDER_PROP_TYPE,POSITION_TYPE_SELL,EQUAL);
            if(list_sell==NULL)
               return;
            //--- Sort the list by profit considering commission and swap
            list_sell.Sort(SORT_BY_ORDER_PROFIT_FULL);
            //--- Get the index of the Sell position with the maximum profit
            int index_sell=CSelect::FindOrderMax(list_sell,ORDER_PROP_PROFIT_FULL);
            if(index_buy>WRONG_VALUE && index_sell>WRONG_VALUE)
              {
               //--- Select the Buy position with the maximum profit
               COrder* position_buy=list_buy.At(index_buy);
               //--- Select the Sell position with the maximum profit
               COrder* position_sell=list_sell.At(index_sell);
               if(position_buy!=NULL && position_sell!=NULL)
                 {
                  //--- If the pending request creation buttons are not pressed, close positions by ticket
                  if(!pressed_pending_close_buy_by_sell)
                     engine.ClosePositionBy((ulong)position_buy.Ticket(),(ulong)position_sell.Ticket());
                  //--- Otherwise, create a pending request for closing a Buy position by an opposite Sell one
                  //--- and set the conditions depending on active buttons
                  else
                    {
                     int id=engine.ClosePositionByPending(position_buy.Ticket(),position_sell.Ticket());
                     if(id>0)
                       {
                        //--- set the pending request activation price and time, as well as set activation parameters
                        double bid=SymbolInfoDouble(NULL,SYMBOL_BID);
                        double price_activation=NormalizeDouble(bid+distance_pending_request*point,digits);
                        ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
                        SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_CLOSE_BUY_BY_SELL,EQUAL_OR_MORE,bid,TimeCurrent());
                       }
                    }
                 }
              }
           }
        }
        
      //--- If the BUTT_CLOSE_SELL button is pressed: Close Sell with the maximum profit
      else if(button==EnumToString(BUTT_CLOSE_SELL))
        {
         //--- Get the list of all open positions
         CArrayObj* list=engine.GetListMarketPosition();
         //--- Select only Sell positions from the list and for the current symbol only
         list=CSelect::ByOrderProperty(list,ORDER_PROP_SYMBOL,Symbol(),EQUAL);
         list=CSelect::ByOrderProperty(list,ORDER_PROP_TYPE,POSITION_TYPE_SELL,EQUAL);
         //--- Sort the list by profit considering commission and swap
         list.Sort(SORT_BY_ORDER_PROFIT_FULL);
         //--- Get the index of the Sell position with the maximum profit
         int index=CSelect::FindOrderMax(list,ORDER_PROP_PROFIT_FULL);
         if(index>WRONG_VALUE)
           {
            //--- Get the Sell position object and close a position by ticket
            COrder* position=list.At(index);
            if(position!=NULL)
              {
               //--- If the pending request creation buttons are not pressed, close a position
               if(!pressed_pending_close_sell)
                  engine.ClosePosition((ulong)position.Ticket());
               //--- Otherwise, create a pending request for closing a position by ticket
               //--- and set the conditions depending on active buttons
               else
                 {
                  int id=engine.ClosePositionPending(position.Ticket());
                  if(id>0)
                    {
                     //--- set the pending request activation price and time, as well as set activation parameters
                     double ask=SymbolInfoDouble(NULL,SYMBOL_ASK);
                     double price_activation=NormalizeDouble(ask-distance_pending_request*point,digits);
                     ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
                     SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_CLOSE_SELL,EQUAL_OR_LESS,ask,TimeCurrent());
                    }
                 }
              }
           }
        }
      //--- If the BUTT_CLOSE_SELL2 button is pressed: Close the half of the Sell with the maximum profit
      else if(button==EnumToString(BUTT_CLOSE_SELL2))
        {
         //--- Get the list of all open positions
         CArrayObj* list=engine.GetListMarketPosition();
         //--- Select only Sell positions from the list and for the current symbol only
         list=CSelect::ByOrderProperty(list,ORDER_PROP_SYMBOL,Symbol(),EQUAL);
         list=CSelect::ByOrderProperty(list,ORDER_PROP_TYPE,POSITION_TYPE_SELL,EQUAL);
         //--- Sort the list by profit considering commission and swap
         list.Sort(SORT_BY_ORDER_PROFIT_FULL);
         //--- Get the index of the Sell position with the maximum profit
         int index=CSelect::FindOrderMax(list,ORDER_PROP_PROFIT_FULL);
         if(index>WRONG_VALUE)
           {
            //--- Get the Sell position object and close a position by ticket
            COrder* position=list.At(index);
            if(position!=NULL)
              {
               //--- If the pending request creation buttons are not pressed, close a position by ticket
               if(!pressed_pending_close_sell2)
                  engine.ClosePositionPartially((ulong)position.Ticket(),position.Volume()/2.0);
               //--- Otherwise, create a pending request for closing a position partially by ticket
               //--- and set the conditions depending on active buttons
               else
                 {
                  int id=engine.ClosePositionPartiallyPending(position.Ticket(),position.Volume()/2.0);
                  if(id>0)
                    {
                     //--- set the pending request activation price and time, as well as set activation parameters
                     double ask=SymbolInfoDouble(NULL,SYMBOL_ASK);
                     double price_activation=NormalizeDouble(ask-distance_pending_request*point,digits);
                     ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
                     SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_CLOSE_SELL2,EQUAL_OR_LESS,ask,TimeCurrent());
                    }
                 }
              }
           }
        }
      //--- If the BUTT_CLOSE_SELL_BY_BUY button is pressed: Close Sell with the maximum profit by the opposite Buy with the maximum profit
      else if(button==EnumToString(BUTT_CLOSE_SELL_BY_BUY))
        {
         //--- In case of a hedging account
         if(engine.IsHedge())
           {
            CArrayObj *list_buy=NULL, *list_sell=NULL;
            //--- Get the list of all open positions
            CArrayObj* list=engine.GetListMarketPosition();
            if(list==NULL)
               return;
            //--- Select only current symbol positions from the list
            list=CSelect::ByOrderProperty(list,ORDER_PROP_SYMBOL,Symbol(),EQUAL);
            
            //--- Select only Sell positions from the list
            list_sell=CSelect::ByOrderProperty(list,ORDER_PROP_TYPE,POSITION_TYPE_SELL,EQUAL);
            if(list_sell==NULL)
               return;
            //--- Sort the list by profit considering commission and swap
            list_sell.Sort(SORT_BY_ORDER_PROFIT_FULL);
            //--- Get the index of the Sell position with the maximum profit
            int index_sell=CSelect::FindOrderMax(list_sell,ORDER_PROP_PROFIT_FULL);
            
            //--- Select only Buy positions from the list
            list_buy=CSelect::ByOrderProperty(list,ORDER_PROP_TYPE,POSITION_TYPE_BUY,EQUAL);
            if(list_buy==NULL)
               return;
            //--- Sort the list by profit considering commission and swap
            list_buy.Sort(SORT_BY_ORDER_PROFIT_FULL);
            //--- Get the index of the Buy position with the maximum profit
            int index_buy=CSelect::FindOrderMax(list_buy,ORDER_PROP_PROFIT_FULL);
            if(index_sell>WRONG_VALUE && index_buy>WRONG_VALUE)
              {
               //--- Select the Sell position with the maximum profit
               COrder* position_sell=list_sell.At(index_sell);
               //--- Select the Buy position with the maximum profit
               COrder* position_buy=list_buy.At(index_buy);
               if(position_sell!=NULL && position_buy!=NULL)
                 {
                  //--- If the pending request creation buttons are not pressed, close positions by ticket
                  if(!pressed_pending_close_sell_by_buy)
                     engine.ClosePositionBy((ulong)position_sell.Ticket(),(ulong)position_buy.Ticket());
                  //--- Otherwise, create a pending request for closing a Sell position by an opposite Buy one
                  //--- and set the conditions depending on active buttons
                  else
                    {
                     int id=engine.ClosePositionByPending(position_sell.Ticket(),position_buy.Ticket());
                     if(id>0)
                       {
                        //--- set the pending request activation price and time, as well as set activation parameters
                        double ask=SymbolInfoDouble(NULL,SYMBOL_ASK);
                        double price_activation=NormalizeDouble(ask-distance_pending_request*point,digits);
                        ulong  time_activation=TimeCurrent()+bars_delay_pending_request*PeriodSeconds();
                        SetPReqCriterion((uchar)id,price_activation,time_activation,BUTT_CLOSE_SELL_BY_BUY,EQUAL_OR_LESS,ask,TimeCurrent());
                       }
                    }
                 }
              }
           }
        }
      //--- If the BUTT_CLOSE_ALL is pressed: Close all positions starting with the one with the least profit
      else if(button==EnumToString(BUTT_CLOSE_ALL))
        {
         //--- Get the list of all open positions
         CArrayObj* list=engine.GetListMarketPosition();
         //--- Select only current symbol positions from the list
         list=CSelect::ByOrderProperty(list,ORDER_PROP_SYMBOL,Symbol(),EQUAL);
         if(list!=NULL)
           {
            //--- Sort the list by profit considering commission and swap
            list.Sort(SORT_BY_ORDER_PROFIT_FULL);

            int total=list.Total();
            //--- In the loop from the position with the least profit
            for(int i=0;i<total;i++)
              {
               COrder* position=list.At(i);
               if(position==NULL)
                  continue;
               //--- close each position by its ticket
               engine.ClosePosition((ulong)position.Ticket());
              }
           }
        }
      //--- If the BUTT_DELETE_PENDING button is pressed: Remove pending orders starting from the oldest one
      else if(button==EnumToString(BUTT_DELETE_PENDING))
        {
         //--- Get the list of all orders
         CArrayObj* list=engine.GetListMarketPendings();
         //--- Select only current symbol orders from the list
         list=CSelect::ByOrderProperty(list,ORDER_PROP_SYMBOL,Symbol(),EQUAL);
         if(list!=NULL)
           {
            //--- Sort the list by placement time
            list.Sort(SORT_BY_ORDER_TIME_OPEN);
            int total=list.Total();
            //--- In a loop from an order with the longest time
            for(int i=total-1;i>=0;i--)
              {
               COrder* order=list.At(i);
               if(order==NULL)
                  continue;
               //--- delete the order by its ticket
               engine.DeleteOrder((ulong)order.Ticket());
              }
           }
        }
      //--- If the BUTT_PROFIT_WITHDRAWAL button is pressed: Withdraw funds from the account
      if(button==EnumToString(BUTT_PROFIT_WITHDRAWAL))
        {
         //--- If the program is launched in the tester
         if(MQLInfoInteger(MQL_TESTER))
           {
            //--- Emulate funds withdrawal
            TesterWithdrawal(withdrawal);
           }
        }
      //--- If the BUTT_SET_STOP_LOSS button is pressed: Place StopLoss to all orders and positions where it is not present
      if(button==EnumToString(BUTT_SET_STOP_LOSS))
        {
         SetStopLoss();
        }
      //--- If the BUTT_SET_TAKE_PROFIT button is pressed: Place TakeProfit to all orders and positions where it is not present
      if(button==EnumToString(BUTT_SET_TAKE_PROFIT))
        {
         SetTakeProfit();
        }
      //--- Wait for 1/10 of a second
      Sleep(100);
      //--- "Unpress" the button (if this is neither a trailing button, nor the buttons enabling pending requests)
      if(button!=EnumToString(BUTT_TRAILING_ALL) && StringFind(button,"_PRICE")<0 && StringFind(button,"_TIME")<0)
         ButtonState(button_name,false);
      //--- If the BUTT_TRAILING_ALL button or the buttons enabling pending requests are pressed
      else
        {
         //--- Set the active button color for the button enabling trailing
         if(button==EnumToString(BUTT_TRAILING_ALL))
           {
            ButtonState(button_name,true);
            trailing_on=true;
           }
         
         //--- Buying
         //--- Set the active button color for the button enabling pending requests for opening Buy by price or time
         if(button==EnumToString(BUTT_BUY)+"_PRICE" || button==EnumToString(BUTT_BUY)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_buy=true;
           }
         //--- Set the active button color for the button enabling pending requests for placing BuyLimit by price or time
         if(button==EnumToString(BUTT_BUY_LIMIT)+"_PRICE" || button==EnumToString(BUTT_BUY_LIMIT)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_buy_limit=true;
           }
         //--- Set the active button color for the button enabling pending requests for placing BuyStop by price or time
         if(button==EnumToString(BUTT_BUY_STOP)+"_PRICE" || button==EnumToString(BUTT_BUY_STOP)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_buy_stop=true;
           }
         //--- Set the active button color for the button enabling pending requests for placing BuyStopLimit by price or time
         if(button==EnumToString(BUTT_BUY_STOP_LIMIT)+"_PRICE" || button==EnumToString(BUTT_BUY_STOP_LIMIT)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_buy_stoplimit=true;
           }
         //--- Set the active button color for the button enabling pending requests for closing Buy by price or time
         if(button==EnumToString(BUTT_CLOSE_BUY)+"_PRICE" || button==EnumToString(BUTT_CLOSE_BUY)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_close_buy=true;
           }
         //--- Set the active button color for the button enabling pending requests for closing 1/2 Buy by price or time
         if(button==EnumToString(BUTT_CLOSE_BUY2)+"_PRICE" || button==EnumToString(BUTT_CLOSE_BUY2)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_close_buy2=true;
           }
         //--- Set the active button color for the button enabling pending requests for closing Buy by an opposite Sell by price or time
         if(button==EnumToString(BUTT_CLOSE_BUY_BY_SELL)+"_PRICE" || button==EnumToString(BUTT_CLOSE_BUY_BY_SELL)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_close_buy_by_sell=true;
           }
         
         //--- Selling
         //--- Set the active button color for the button enabling pending requests for opening Sell by price or time
         if(button==EnumToString(BUTT_SELL)+"_PRICE" || button==EnumToString(BUTT_SELL)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_sell=true;
           }
         //--- Set the active button color for the button enabling pending requests for placing SellLimit by price or time
         if(button==EnumToString(BUTT_SELL_LIMIT)+"_PRICE" || button==EnumToString(BUTT_SELL_LIMIT)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_sell_limit=true;
           }
         //--- Set the active button color for the button enabling pending requests for placing SellStop by price or time
         if(button==EnumToString(BUTT_SELL_STOP)+"_PRICE" || button==EnumToString(BUTT_SELL_STOP)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_sell_stop=true;
           }
         //--- Set the active button color for the button enabling pending requests for placing SellStopLimit by price or time
         if(button==EnumToString(BUTT_SELL_STOP_LIMIT)+"_PRICE" || button==EnumToString(BUTT_SELL_STOP_LIMIT)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_sell_stoplimit=true;
           }
         //--- Set the active button color for the button enabling pending requests for closing Sell by price or time
         if(button==EnumToString(BUTT_CLOSE_SELL)+"_PRICE" || button==EnumToString(BUTT_CLOSE_SELL)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_close_sell=true;
           }
         //--- Set the active button color for the button enabling pending requests for closing 1/2 Sell by price or time
         if(button==EnumToString(BUTT_CLOSE_SELL2)+"_PRICE" || button==EnumToString(BUTT_CLOSE_SELL2)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_close_sell2=true;
           }
         //--- Set the active button color for the button enabling pending requests for closing Sell by an opposite Buy by price or time
         if(button==EnumToString(BUTT_CLOSE_SELL_BY_BUY)+"_PRICE" || button==EnumToString(BUTT_CLOSE_SELL_BY_BUY)+"_TIME")
           {
            ButtonState(button_name,true);
            pressed_pending_close_sell_by_buy=true;
           }
        }
      //--- re-draw the chart
      ChartRedraw();
     }
   //--- Return a color for the inactive buttons
   else 
     {
      //--- trailing button
      if(button==EnumToString(BUTT_TRAILING_ALL))
        {
         ButtonState(button_name,false);
         trailing_on=false;
        }
      
      //--- Buying
      //--- the button enabling pending requests for opening Buy by price
      if(button==EnumToString(BUTT_BUY)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_buy=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_BUY)+"_TIME"));
        }
      //--- the button enabling pending requests for opening Buy by time
      if(button==EnumToString(BUTT_BUY)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_buy=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_BUY)+"_PRICE"));
        }
      
      //--- the button enabling pending requests for placing BuyLimit by price
      if(button==EnumToString(BUTT_BUY_LIMIT)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_buy_limit=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_BUY_LIMIT)+"_TIME"));
        }
      //--- the button enabling pending requests for placing BuyLimit by time
      if(button==EnumToString(BUTT_BUY_LIMIT)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_buy_limit=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_BUY_LIMIT)+"_PRICE"));
        }
      
      //--- the button enabling pending requests for placing BuyStop by price
      if(button==EnumToString(BUTT_BUY_STOP)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_buy_stop=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_BUY_STOP)+"_TIME"));
        }
      //--- the button enabling pending requests for placing BuyStop by time
      if(button==EnumToString(BUTT_BUY_STOP)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_buy_stop=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_BUY_STOP)+"_PRICE"));
        }
      
      //--- the button enabling pending requests for placing BuyStopLimit by price
      if(button==EnumToString(BUTT_BUY_STOP_LIMIT)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_buy_stoplimit=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_BUY_STOP_LIMIT)+"_TIME"));
        }
      //--- the button enabling pending requests for placing BuyStopLimit by time
      if(button==EnumToString(BUTT_BUY_STOP_LIMIT)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_buy_stoplimit=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_BUY_STOP_LIMIT)+"_PRICE"));
        }
      
      //--- the button enabling pending requests for closing Buy by price
      if(button==EnumToString(BUTT_CLOSE_BUY)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_close_buy=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_CLOSE_BUY)+"_TIME"));
        }
      //--- the button enabling pending requests for closing Buy by time
      if(button==EnumToString(BUTT_CLOSE_BUY)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_close_buy=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_CLOSE_BUY)+"_PRICE"));
        }
      
      //--- the button enabling pending requests for closing 1/2 Buy by price
      if(button==EnumToString(BUTT_CLOSE_BUY2)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_close_buy2=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_CLOSE_BUY2)+"_TIME"));
        }
      //--- the button enabling pending requests for closing 1/2 Buy by time
      if(button==EnumToString(BUTT_CLOSE_BUY2)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_close_buy2=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_CLOSE_BUY2)+"_PRICE"));
        }
      
      //--- the button enabling pending requests for closing Buy by an opposite Sell by price
      if(button==EnumToString(BUTT_CLOSE_BUY_BY_SELL)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_close_buy_by_sell=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_CLOSE_BUY_BY_SELL)+"_TIME"));
        }
      //--- the button enabling pending requests for closing Buy by an opposite Sell by time
      if(button==EnumToString(BUTT_CLOSE_BUY_BY_SELL)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_close_buy_by_sell=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_CLOSE_BUY_BY_SELL)+"_PRICE"));
        }

      //--- Selling
      //--- the button enabling pending requests for opening Sell by price
      if(button==EnumToString(BUTT_SELL)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_sell=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_SELL)+"_TIME"));
        }
      //--- the button enabling pending requests for opening Sell by time
      if(button==EnumToString(BUTT_SELL)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_sell=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_SELL)+"_PRICE"));
        }
      
      //--- the button enabling pending requests for placing SellLimit by price
      if(button==EnumToString(BUTT_SELL_LIMIT)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_sell_limit=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_SELL_LIMIT)+"_TIME"));
        }
      //--- the button enabling pending requests for placing SellLimit by time
      if(button==EnumToString(BUTT_SELL_LIMIT)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_sell_limit=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_SELL_LIMIT)+"_PRICE"));
        }
      
      //--- the button enabling pending requests for placing SellStop by price
      if(button==EnumToString(BUTT_SELL_STOP)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_sell_stop=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_SELL_STOP)+"_TIME"));
        }
      //--- the button enabling pending requests for placing SellStop by time
      if(button==EnumToString(BUTT_SELL_STOP)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_sell_stop=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_SELL_STOP)+"_PRICE"));
        }
      
      //--- the button enabling pending requests for placing SellStopLimit by price
      if(button==EnumToString(BUTT_SELL_STOP_LIMIT)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_sell_stoplimit=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_SELL_STOP_LIMIT)+"_TIME"));
        }
      //--- the button enabling pending requests for placing SellStopLimit by time
      if(button==EnumToString(BUTT_SELL_STOP_LIMIT)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_sell_stoplimit=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_SELL_STOP_LIMIT)+"_PRICE"));
        }
      
      //--- the button enabling pending requests for closing Sell by price
      if(button==EnumToString(BUTT_CLOSE_SELL)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_close_sell=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_CLOSE_SELL)+"_TIME"));
        }
      //--- the button enabling pending requests for closing Sell by time
      if(button==EnumToString(BUTT_CLOSE_SELL)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_close_sell=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_CLOSE_SELL)+"_PRICE"));
        }
      
      //--- the button enabling pending requests for closing 1/2 Sell by price
      if(button==EnumToString(BUTT_CLOSE_SELL2)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_close_sell2=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_CLOSE_SELL2)+"_TIME"));
        }
      //--- the button enabling pending requests for closing 1/2 Sell by time
      if(button==EnumToString(BUTT_CLOSE_SELL2)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_close_sell2=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_CLOSE_SELL2)+"_PRICE"));
        }
      
      //--- the button enabling pending requests for closing Sell by an opposite Buy by price
      if(button==EnumToString(BUTT_CLOSE_SELL_BY_BUY)+"_PRICE")
        {
         ButtonState(button_name,false);
         pressed_pending_close_sell_by_buy=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_CLOSE_SELL_BY_BUY)+"_TIME"));
        }
      //--- the button enabling pending requests for closing Sell by an opposite Buy by time
      if(button==EnumToString(BUTT_CLOSE_SELL_BY_BUY)+"_TIME")
        {
         ButtonState(button_name,false);
         pressed_pending_close_sell_by_buy=(ButtonState(button_name) | ButtonState(prefix+EnumToString(BUTT_CLOSE_SELL_BY_BUY)+"_PRICE"));
        }
      //--- re-draw the chart
      ChartRedraw();
     }
  }
//+------------------------------------------------------------------+

Todos os blocos de código substituídos e os novos adicionados estão amplamente comentados, e acho que tudo está claro.
Em qualquer caso, na discussão do artigo podem ser tiradas todas as dúvidas que surgirem.

Compilemos o EA e testemos a operação de solicitações pendentes para vários tipos de fechamento de posições (parcial, completa e mediante posição oposta). Para fazer isso, iniciamos o EA no testador visual e executamos as seguintes operações:

1. abrimos uma posição de venda e criamos uma solicitação pendente para fechar parte dessa posição segundo o valor do preço;
   
2. após o fechamento parcial de uma posição curta, abrimos uma posição de compra e criamos uma solicitação pendente para fechar essa posição com uma posição oposta, ou seja, para encerramento mediante uma posição curta semi-fechada segundo o valor do preço;
   
3. após fechar parte da posição longa com a posição oposta de venda, criamos uma nova solicitação pendente para fechar completamente a posição longa com a condição de que a solicitação seja ativada segundo o tempo.

O que vem agora?

No próximo artigo, continuaremos a desenvolver o conceito de solicitações de negociação pendentes e implementaremos a remoção de ordens pendentes e a modificação de ordens e posições por condições.

Complementos

Artigos desta série:

Parte 1. Conceito, gerenciamento de dados e primeiros resultados
Parte 2. Coleção do histórico de ordens e negócios
Parte 3. Coleção de ordens e posições de mercado, busca e ordenação
Parte 4. Eventos de Negociação. Conceito
Parte 5. Classes e coleções de eventos de negociação. Envio de eventos para o programa
Parte 6. Eventos da conta netting
Parte 7. Eventos de ativação da ordem stoplimit, preparação da funcionalidade para os eventos de modificação de ordens e posições
Parte 8. Eventos de modificação de ordens e posições
Parte 9. Compatibilidade com a MQL4 — preparação dos dados
Parte 10. Compatibilidade com a MQL4 — eventos de abertura de posição e ativação de ordens pendentes
Parte 11. Compatibilidade com a MQL4 — eventos de encerramento de posição
Parte 12. Implementação da classe de objeto "conta" e da coleção de objetos da conta
Parte 13. Eventos do objeto conta
Parte 14. O objeto símbolo
Parte 15. Coleção de objetos-símbolos
Parte 16. Eventos de coleção de símbolos
Parte 17. Interatividade de objetos de biblioteca
Parte 18. Interatividade do objeto-conta e quaisquer de outros objetos da biblioteca
Parte 19. Classe de mensagens de biblioteca
Parte 20. Criação e armazenamento de recursos de programas
Parte 21 Classes de negociação - objeto base de negociação multiplataforma
Parte 22. Classes de negociação - classe básica de negociação, controle de restrições
Parte 23. Classes de negociação - classe básica de negociação, controle de parâmetros válidos
Parte 24. Classes de negociação - classe básica de negociação, correção automática de parâmetros errados
Parte 25. Classes de negociação - classe básica de negociação, processamento de erros retornados pelo servidor de negociação
Parte 26. Trabalho com ordens pendentes, primeira implementação (abertura de posições)
Parte 27. Trabalho com ordens pendentes, posicionamento de ordens pendentes Parte 28. Trabalho com ordens pendentes de negociação - fechamento, exclusão, modificações
Parte 29. Trabalho com ordens de negociação pendentes, classes de objetos-ordens
Parte 30. Trabalho com ordens de negociação pendentes, gerenciamento de objetos-ordens
Parte 31. Trabalho com ordens de negociação pendentes, abertura de posições por condições
Parte 32. Trabalho com ordens de negociação pendentes, posicionando ordens pendentes por condições