metatrader debugging EA using DEBUGview - great for beginners to learn

You can download Debug view from Microsoft to externalise anything in your code to help debug it . I have learned a great deal about MT4 from using this tool simply to output the results of some code so I understand what it is doing . For example you may see some code that you do not understand but can output parts of it and keep a track of what each calculation does ..essentially slowing it down to understand.

I adapted this from somebody else who wrote log( " " ) so thank you to that person. I have since created some new functions to make it easier to control what I see .

Process-

## IMPORTANT NOTE ##

Please test this in a DEMOtrade account until you understand what is happening .

STEP 1) download the debug view program above

STEP 2) Insert this MT4 code below in your MT4 meta editor and save it in your "INCLUDE" folder.

//
// send information to OutputDebugString() to be viewed and logged by
// SysInternal's DebugView (free download from Microsoft) This is ideal for
// debugging as an alternative to Print(). The function will take up to 10
// strings (or numeric) arguments to be concatenated into one debug message.
// http://technet.microsoft.com/en-us/sysinternals/bb896647.aspx
//
//         #property indicator_separate_window

#import "kernel32.dll"                 // for debug commands
void OutputDebugStringW(string msg);   // for debug commands
#import 


//|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
//|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
// FUNCTION log

void log(   string s1,    string s2="",    string s3="",    string s4="",    string s5="", 
   string s6="",    string s7="",    string s8="")

{
   string out = StringTrimRight(StringConcatenate(" |||| ",
      WindowExpertName(), " ||||", " ", Symbol()," |||| ", 
      " ", s1, 
      " ", s2, 
      " ", s3, 
      " ", s4, 
      " ", s5, 
      " ", s6, 
      " ", s7, 
      " ", s8
   ));
   //string out1 = StringTrimRight(StringConcatenate( "++++++++++++++++"   ));
    OutputDebugStringW(out);
    //OutputDebugStringW(out1);
    
}
//|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
//|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
// FUNCTION log symbol

void logs(   string s1,    string s2="",    string s3="",    string s4="",    string s5="", 
   string s6="",    string s7="",    string s8="")

{
   string out = StringTrimRight(StringConcatenate(" |||| ", Symbol()," |||| ", 
      " ", s1, 
      " ", s2, 
      " ", s3, 
      " ", s4, 
      " ", s5, 
      " ", s6, 
      " ", s7, 
      " ", s8
   ));
   //string out1 = StringTrimRight(StringConcatenate( "++++++++++++++++"   ));
    OutputDebugStringW(out);
    //OutputDebugStringW(out1);
    
}
    
//|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
//|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
//   FUNCTION logB- blank details 

void logb(   string s1,    string s2="",    string s3="",    string s4="",    string s5="", 
   string s6="",    string s7="",    string s8="")

{
 
   string out1 = StringTrimRight(StringConcatenate("~" 
      " ", s1, 
      " ", s2, 
      " ", s3, 
      " ", s4, 
      " ", s5, 
      " ", s6, 
      " ", s7, 
      " ", s8
   ));
   //string out1 = StringTrimRight(StringConcatenate( "++++++++++++++++"   ));
    OutputDebugStringW(out1);
    //OutputDebugStringW(out1);
    
}

//|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
//|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
// FUNCTION logN -file name 

void logn(   string s1,    string s2="",    string s3="",    string s4="",    string s5="", 
   string s6="",    string s7="",    string s8="")

{
   string out = StringTrimRight(StringConcatenate(" |||| ",
      WindowExpertName()," ||||", 
      " ", s1, 
      " ", s2, 
      " ", s3, 
      " ", s4, 
      " ", s5, 
      " ", s6, 
      " ", s7, 
      " ", s8
   ));
   //string out1 = StringTrimRight(StringConcatenate( "++++++++++++++++"   ));
    OutputDebugStringW(out);
    //OutputDebugStringW(out1);
    
}

//|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
//|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
// FUNCTION logT1 - uses taged names for DEBUG COLOUR quick easy to identify

void logt1(   string s1,    string s2="",    string s3="",    string s4="",    string s5="", 
   string s6="",    string s7="",    string s8="")

{
   string out = StringTrimRight(StringConcatenate(" |||| tag1 ||||", 
      " ", s1, 
      " ", s2, 
      " ", s3, 
      " ", s4, 
      " ", s5, 
      " ", s6, 
      " ", s7, 
      " ", s8
   ));
   //string out1 = StringTrimRight(StringConcatenate( "++++++++++++++++"   ));
    OutputDebugStringW(out);
    //OutputDebugStringW(out1);
    
}
//|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
//|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
// FUNCTION logT2 - uses taged names for DEBUG COLOUR quick easy to identify

void logt2(   string s1,    string s2="",    string s3="",    string s4="",    string s5="", 
   string s6="",    string s7="",    string s8="")

{
   string out = StringTrimRight(StringConcatenate(" |||| tag2 ||||", 
      " ", s1, 
      " ", s2, 
      " ", s3, 
      " ", s4, 
      " ", s5, 
      " ", s6, 
      " ", s7, 
      " ", s8
   ));
   //string out1 = StringTrimRight(StringConcatenate( "++++++++++++++++"   ));
    OutputDebugStringW(out);
    //OutputDebugStringW(out1);
    
}



   

STEP 3) cut and past this demo EA to meta editor,save it to Expert adviser folder and run compile, this helps understand how to use log functions

//+------------------------------------------------------------------+
//|                                               zzz_Debug_test.mq4 |
//|                        Copyright 2013, MetaQuotes Software Corp. |
//|                                              https://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "dasser  - in MQL4.com forum "
#property link      "https://www.mql5.com"
#property version   "1.00"
#property strict
#include <debug_inc.mqh>


//+------------------------------------------------------------------+
//| Expert initialization function                                   |
//+------------------------------------------------------------------+
int OnInit()
  {
//---
   
//---
   return(INIT_SUCCEEDED);
  }
//+------------------------------------------------------------------+
//| Expert deinitialization function                                 |
//+------------------------------------------------------------------+
void OnDeinit(const int reason)
  {
//---
   
  }
//+------------------------------------------------------------------+
//| Expert tick function                                             |
//+------------------------------------------------------------------+
void OnTick()
  {
                  logb(" blank log "); // no information added 
                  log(" standard log "); // adds symbol and file information
                  logs(" symbol log  "); // adds symbol in line 
                  logn(" file name log "); //adds filename in line 
                  logt1(" tag1 log  "); // adds tag1 as text to filter colour
                  logt2(" tag2 log "); // adds tag1 as text to filter colour
                  logb("  blank log  ") ;// no information added

                  logb("Symbol() = ", Symbol()) ; // demo showing how to add paramters 
                  logb(" OrdersTotal() = ", OrdersTotal()) ;// demo showing how to add paramters
                  logt1("Symbol() = ", Symbol()) ;
                  logt2(" OrdersTotal() = ", OrdersTotal()) ;
                  logn("Symbol() = ", Symbol()) ;
                  logn(" OrdersTotal() = ", OrdersTotal()) ;
   
  }
//+------------------------------------------------------------------+

STEP 4 - Find The EA you just saved and drag it onto a blank worksheet chart

STEP 5 - Open the debug view program you downloaded in earlier steps

STEP 6 - you should now see demonstration of the log showing text and EA functions like Symbol() and OrdersTotal() .

STEP 7 - Open a position ( if you don't ) and see the OrdersTotal() change showing how many orders you have open.

STEP 8 - with any new EA you build at the top place this code at the start of the EA

#include <debug_inc.mqh>

This adds the debug functions to you ea code and now you can use the functions in such as loga( " ");, logt1("..") etc ;

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Below is an example showing debug view in action ..

Here I calculate my open positions maximum profit and maximum loss amounts, and the ratio,

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Notice in the EA posted .. OrdersTotal() function even counts pending orders ( something I was made aware of by using this log function )

Hope this helps people ... let me know of any better ideas .