CDir (MT5) - a class for getting directory contents - library for MetaTrader 5

Sometimes it is necessary to go beyond the sandbox and read the contents to check the existence of a file or directory in the file system. Also, you may need to find a file or directory attributes, file size, creation time, last access or writing. The following code shows an example of how to solve these problems:

A standard prologue and description of variables, as well as a link to the source code of the #include <WIN_API\Dir_API.mqh> include class is am implicit instruction to the compiler that it should look for the file in the folder \MQL5\Include\WIN_API. You are free to change this link, depending on your preference in the organization of work with include files in accordance with the documentation.

//+------------------------------------------------------------------+
//|                                            ExampleDirClass.mq4/5 |
//|                                        Copyright © 2017, Avatara |
//|                            https://www.mql5.com/en/users/avatara |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2017, Avatara"            2017/02/12
#property link      "https://www.mql5.com/en/users/avatara"
#property description "-- Example Dir Class --------------"
#property strict
#include <WIN_API\Dir_API.mqh> 
//+------------------------------------------------------------------+
//| Script program start function                                    |
//+------------------------------------------------------------------+
void OnStart()
  {
   File_Def File;            // work structure
   CDir Dir; int total,i;     
   string path = TerminalInfoString(TERMINAL_COMMONDATA_PATH)+
               "\\..\\..\\Terminal";
//---    
  

As we can see, the string variable path contains the path to the folder, which is two levels above the standard location of the running terminal directory, and we (if the /portable option is not used) obtain the path to the directory that contains the user data of all the client terminals of that user.

A thoughtful reader would say that we do extra movements - that it could be enough to get one level up in order to go to the right directory. But what if we want to navigate to another folder, for example Crashes or Tester? This is a more instructive example.

Let us get back to the example code.

/---    
   total = Dir.Create(path);       // init dir
   Print (path," Total=",total-3); //Common,Help && Community not calc
    for (i = 0;i<total;i++)
    {
     string nameFile = Dir.GetNameFile(i);
     if(nameFile == "Common"||nameFile=="Help"||nameFile=="Community")
                                                              continue;
     File = Dir.GetStruct(i);
     Print (StringFormat ("%37s \t%8X\t  %5s\t",nameFile,
     File.FileAttributes,File.isDir?"-SubDir-":""),
     File.isDir?"            ":IntegerToString(File.FileLength,12),
     File.CreationTime,"     ",File.LastWriteTime,"     ",
     File.LastAccessTime);
    }
    Dir.Clear(); 
//---    

Having created a class instance, we receive the number of element (files and subdirectories) in the total variable. By organizing a loop we can print the list of directories of terminals (skipping shared directories). Let us illustrate access to the instance data by accessing a copy of the working data structure of the File class.

  path=TerminalInfoString(TERMINAL_PATH)+
              "\\..";
    Dir.Create(path,"\\M*");   // use filter "M*"       
    Print ("Alternative access:");
    total = Dir.Size(); 
    Print (Dir.Path," Total=",total);
    for (i = 0;i<total;i++)
    {
    Print  (StringFormat("%57s \t%8X \t %s \t",Dir.GetNameFile(i), 
                         Dir.GetStruct(i).FileAttributes,
                         Dir.isDir(i)?"--- SubDir ---": 
                         IntegerToString(Dir.GetFileLength(i),14)),
    "\t   Last modify: ",Dir.GetLastWriteTime(i));
    }
//---    
    Dir.Clear();  

The example of printing part of directory contents (using the selection of elements containing the M letter at the beginning) demonstrates other methods for working with the class members.

In the following part of code, we check the existence of the specific file and find out its length.

//---  Use to check the file
    path="C:";
    Print("------------ Use to check the file ---------------------");
    stringfilter="\\pagefile.sys";
    Dir.Create(path,filter);
    total=Dir.Size();
    PrintFormat("Find %d entry.",total);
    if(total>0)
      for(i =0;i<total;i++)Print("File search \"",path,filter,
        "\" is return:",Dir.isDir(i)?"--- SubDir ---  "+
        Dir.GetNameFile(i):Dir.GetNameFile(i)+
        IntegerToString(Dir.GetFileLength(i),14)+" byte. \t",
        StringFormat("Atributes=%X",Dir.GetAtributes(i)));
    else  Print("File ",path,filter," is absent.");
//---
    Dir.Clear();              

The test script ends with an example of using references to an instance of the class storing the directory contents element:

  //--- use pointer to access data
   path="C:\\Temp";
    //---------------------> pointer declarate
    CDir_API *e;
  
    Print("------ Pointer use example. --------");
    total =Dir.Create(path);
    PrintFormat("%s       Find %d entry.",path,total);
    if(total>0)
      for(i =0;i<total;i++)
      {
      e=Dir.GetPointers(i);
      Print(StringFormat("%77s \t%8X\t  %5s\t ",e.Name_File,
          e.FileDef.FileAttributes,e.FileDef.isDir?"-SubDir-":""),
          e.FileDef.isDir?"         ":
          IntegerToString(e.FileDef.FileLength,12),"   ",
          e.FileDef.CreationTime,"     ",
          e.FileDef.LastWriteTime,"     ",
          e.FileDef.LastAccessTime);
      }  
    else  Print("File ",path,filter," is absent.");
//---
    Dir.Clear();
    Print("------------- The end. -----------------------");
}
//+------------------------------------------------------------------+

I have no doubt that most readers will use this method for accessing class data in their work.

Additional information might be needed for understanding attributes:

I hope that this example and the class itself will be useful to you.

Enjoy it!