Discussion of article "Step-by-Step Guide to Writing an Expert Advisor in MQL5 for Beginners" - page 22

[dhlaldo]

Good morning, If someone could help me please. To my understanding, I did everything that is indicated in the article. But I can not manage to have two simultaneous open operations, beyond what I understand that the author wanted to do not to place buy if there was already buy or sell if there was already sell. My strategy, for example, sends a sell signal when I have an open buy order, and instead of opening a sale, the code closes the buy operation without it being able to touch the tp/sl. And so I am left with no buy or sell. The sell closes buy and buy closes sell. I am using only one pair, only one time frame and only one lot size in my strategy. Can you tell me how I can have buy and sell open at the same time if it triggers the strategy? That is to say, that the orders are ONLY closed by tp/sl. Thank you very much in advance.

[Aleksandr Zakhvatkin]

Great article!

[Arthur Vieira]

Sella170:
Does anyone know if I can use this EA for mini-indexes or mini-dollars?

Yes, you can use the EA by dragging the mouse to the chart or menu > insert > Expert advisor > {nomedoseurobo}.

I hope your question has been answered.

[zrwhiteley]

Many thanks for the excellent article. Where and how would one implement the Intraday Time Filter module into your code?

[Vitor Gama Barreto]

Hi guys, good morning.

I'm in the"Strategy Tester" with this file from the end of the Guide and it shows the following error:

*the error has already been discussed here in this article, but no written solution has worked for me and I need your help.

OF      0       12:44:39.040    EA_ADX (XAUUSD,H1)      2020.01.03 19:00:00   Alert: The Buy order request could not be completed -error:4756
ED      2       12:44:39.043    Trades  2020.01.03 20:00:00   failed market buy 0.1 XAUUSD sl: 1549.09 tp: 1549.16 [Invalid stops]
JP      0       12:44:39.043    EA_ADX (XAUUSD,H1)      2020.01.03 20:00:00   Alert: The Buy order request could not be completed -error:4756
ER      2       12:44:39.049    Trades  2020.01.03 21:00:00   failed market buy 0.1 XAUUSD sl: 1549.90 tp: 1549.97 [Invalid stops]
MR      0       12:44:39.049    EA_ADX (XAUUSD,H1)      2020.01.03 21:00:00   Alert: The Buy order request could not be completed -error:4756
PP      2       12:44:39.053    Trades  2020.01.03 22:00:00   failed market buy 0.1 XAUUSD sl: 1548.16 tp: 1548.23 [Invalid stops]

The file is at the end of the Guide.

How can I solve this problem?

[Alirzea]

surfdoode2:

I also still have this error having made both suggested corrections:

ZeroMemory(mrequest);

and also

if(Buy_opened || Sell_opened)

Please can someone help with the error 4756? It just seems unable to place a Buy Order.

Check if you used the SymbolInfoTick function and wrote this part of the code:

//--- Get the last price quote using the MQL5 MqlTick Structure
   if(!SymbolInfoTick(_Symbol,latest_price))
     {
      Alert("Error getting the latest price quote - error:",GetLastError(),"!!");
      return;
     }

[Régis Amaral]

There is an error in the logic of the algorithm here:

 //--- Do we have positions opened already?
     bool Buy_opened= false ;   // variable to hold the result of Buy opened position
     bool Sell_opened= false ; // variable to hold the result of Sell opened position
    
     if ( PositionSelect ( _Symbol ) == true )   // we have an opened position
    {
         if ( PositionGetInteger ( POSITION_TYPE ) == POSITION_TYPE_BUY )
         {
            Buy_opened = true ;   //It is a Buy
         }
         else if ( PositionGetInteger ( POSITION_TYPE ) == POSITION_TYPE_SELL )
         {
            Sell_opened = true ; // It is a Sell
         }
    }

Since PositionSelect selects the first position for _Symbol, if the EA opens a buy position, the Sell_opened variable will always be false while the buy position is open, causing multiple sell positions to be realised whenever there is a sell signal.

To correct this and know if there are buy and sell positions open simultaneously, the following logic can be used:

 //--- Do we have positions opened already?
   bool Buy_opened = false ;   // variable to hold the result of Buy opened position
   bool Sell_opened = false ; // variables to hold the result of Sell opened position

   if ( PositionSelect ( _Symbol ) == true ) // we have an opened position
   {
       for ( int i= 0 ;i< PositionsTotal ();i++){
	 
         PositionSelectByTicket ( PositionGetTicket (i));

         if ( PositionGetInteger ( POSITION_TYPE ) == POSITION_TYPE_SELL )
         {
            Sell_opened = true ; // It is a Sell
         } else if ( PositionGetInteger ( POSITION_TYPE ) == POSITION_TYPE_BUY )
         {
            Buy_opened = true ; //It is a Buy
         }
      }
   

[Régis Amaral]

Vitor Gama Barreto:

Hello everyone, good morning.

I'm in the"Strategy Tester" with this file from the end of the Guide and it shows the following error:

*the error has already been discussed here in this article, but no written solution has worked for me and I need your help.

The file is at the end of the Guide.

How can I solve this problem?

Check the sale price you are requesting, to do this use breakpoint to debug the mrequest.price, mrequest.sl and mrequest.tp variables.

Try changing

mrequest.type_filling = ORDER_FILLING_FOK;                               // Order execution type

to:

mrequest.type_filling = ORDER_FILLING_IOC;                               // Order execution type

Some papers have minimum stop loss rules, read more here: https://www.mql5.com/pt/forum/319474

[maabypm]

Hello,

Thank you very much for the article Samuel, you are a crack!

It was a bit difficult to get it to work with my broker because the article is in "net" mode and I had to look for information to put it in "hedging" mode. The first problem I encountered was with the mrequest.type_filling .

For the XM broker, the one that works is:

mrequest.type_filling = ORDER_FILLING_IOC;                                          // Type of execution of the order

If you don't know which one your MT5 allows, my recommendation is to use the TypeFilling() functionin a Print(TypeFilling()) or a Comment( TypeFilling()) and it returns the type; if it tells you it is 1 (ORDER_FILLING_FOK) or 2 (ORDER_FILLING_IOC) you know which one you have to put(https://www.mql5.com/docs/constants/tradingconstants/orderproperties#enum_order_type_filling) becauseORDER_FILLING_FOK (1) doesn't work for me with this broker.

Once that is fixed, the problem is that PositionSelect opens a lot of positions. Although Samuel doesn't say it in his strategy, I understand that the objective is to open a single buy or sell position (whichever comes first) with the established criteria (the 4 boolean steps) and that until this position is closed, we can't open another one.

What I have done is to change this code ...

//--- we have no errors, so we continue.
//--- Do we have open positions yet?
    bool Buy_opened=false;  // variable storing the result of the open position Purchase
    bool Sell_opened=false; // variable storing the result of the open position Sale
    
    if (PositionSelect(_Symbol) ==true)  // we have an open position
    {
         if (PositionGetInteger(POSITION_TYPE) == POSITION_TYPE_BUY)
         {
            Buy_opened = true;  // It's a Purchase
         }
         else if(PositionGetInteger(POSITION_TYPE) == POSITION_TYPE_SELL)
         {
            Sell_opened = true; // It's a Sale
         }
    }

For this one...

//--- We have no errors so we continue.
//--- Do we have open positions yet?
   bool Buy_opened = false;               // Variable storing the result of the open Buy position
   bool Sell_opened = false;              // Variable storing the result of the open Sell position
   
   // Let's go through all the orders to see if there are any open ones.
   for(int i = 0; i < PositionsTotal(); i++)   
        {
         ulong ticket = PositionGetTicket(i);
         PositionSelectByTicket(ticket);
    
    if(PositionGetInteger(POSITION_TYPE) == POSITION_TYPE_BUY)
         {
          Buy_opened = true;       // is a purchase
         }
         else if(PositionGetInteger(POSITION_TYPE) == POSITION_TYPE_SELL)
         {
          Sell_opened = true;      // is a sale
         }
   }

// if there is an open position we wait until the active operation is closed (touching the SL or theTP).
   if (Buy_opened || Sell_opened) return; 

Note: Just after comes the line...

//--- Copy the closing price from the previous bar to the current bar, which is bar1.
   p_close=mrate[1].close;

This way it worked fine for me. I hope you find it useful.

Best regards.

[Bin]

surfdoode2:

I also still have this error having made both suggested corrections:

ZeroMemory(mrequest);

and also

if(Buy_opened || Sell_opened)

Please can someone help with the error 4756? It just seems unable to place a Buy Order.

Maybe the Filling Type of your Broker  is ORDER_FILLING_IOC , you can try to edit the code from:

mrequest.type_filling = ORDER_FILLING_FOK;

To:

mrequest.type_filling = ORDER_FILLING_IOC;

I had the same problem and now I solved it successfully