Writing bid-ask prices on a csv file

[hardhu]

Hello everybody,

what I would like to do is to write a simple expert advisor that does this three steps:

1) open a csv file for writing;

2) writes bid and ask prices in that csv files, in different lines;

3) closes the file.

 

I would like to put these three steps respectively in OnInit, OnTick and OnDeinit function, but I am not able to pass the filehandle of the file from OnInit to the other two functions, can anybody help me? Here's my code:

 

void OnInit()
  {
   ResetLastError();
   int filehandle=FileOpen("bidask.csv",FILE_WRITE|FILE_CSV);
   if(filehandle!=INVALID_HANDLE)
     {      
      Print("File correctly opened");
     }
   else Print("Errorin opening file,",GetLastError());
    }

void OnTick()
  {
   MqlTick last_tick;
   if(SymbolInfoTick(Symbol(),last_tick))
     {
     Print(last_tick.time,": Bid = ",last_tick.bid,
            " Ask = ",last_tick.ask,");

      FileWrite(filehandle,last_tick.bid,last_tick.ask);
     }
   else Print("SymbolInfoTick() failed, error = ",GetLastError());
    }

void OnDeinit()
  {
  FileClose(filehandle);
  }

[Alain Verleyen]

hardhu:

Hello everybody,

what I would like to do is to write a simple expert advisor that does this three steps:

1) open a csv file for writing;

2) writes bid and ask prices in that csv files, in different lines;

3) closes the file.

 

I would like to put these three steps respectively in OnInit, OnTick and OnDeinit function, but I am not able to pass the filehandle of the file from OnInit to the other two functions, can anybody help me? Here's my code:

 

You have to use a global variable for your file handle.

[hardhu]

angevoyageur:
You have to use a global variable for your file handle.

Thanks for your suggestion. So, is in your opinion this modification the proper way to use a global variable?

int indfile;

int OnInit()
  {
   ResetLastError();
   int filehandle=FileOpen("bidask.csv",FILE_WRITE|FILE_CSV);
   if(filehandle!=INVALID_HANDLE)
     {      
      Print("File opened correctly");
     }
   else Print("Error in opening file,",GetLastError());
   indfile=filehandle;
   return(INIT_SUCCEEDED);
    }


void OnTick()
{
    MqlTick last_tick;
   if(SymbolInfoTick(Symbol(),last_tick))
     {
     Print(last_tick.time,": Bid = ",last_tick.bid,
            " Ask = ",last_tick.ask,"  Volume = ",last_tick.volume);

      FileWrite(indfile,last_tick.bid,last_tick.ask);
     }
   else Print("SymbolInfoTick() failed, error = ",GetLastError());
  }
  
 

void OnDeinit(const int reason)
  {
 FileClose(indfile);
  }

[Alain Verleyen]

hardhu:

Thanks for your suggestion. So, is in your opinion this modification the proper way to use a global variable?

That should work, but why add an other variable ? you can define filehandle as global.

int filehandle;

int OnInit()
  {
   ResetLastError();
   filehandle=FileOpen("bidask.csv",FILE_WRITE|FILE_CSV);
   if(filehandle!=INVALID_HANDLE)
     {      
      Print("File opened correctly");
     }
   else Print("Error in opening file,",GetLastError());

   return(INIT_SUCCEEDED);
    }
void OnTick()
{
    MqlTick last_tick;
   if(SymbolInfoTick(Symbol(),last_tick))
     {
     Print(last_tick.time,": Bid = ",last_tick.bid,
            " Ask = ",last_tick.ask,"  Volume = ",last_tick.volume);

      FileWrite(filehandle,last_tick.bid,last_tick.ask);
     }
   else Print("SymbolInfoTick() failed, error = ",GetLastError());
  }
  
 

void OnDeinit(const int reason)
  {
 FileClose(filehandle);
  }