//+------------------------------------------------------------------+
//|                                                   SymbolInfo.mq4 |
//|                                                         BlueRain |
//|                                             https://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "BlueRain"
#property link      "https://www.mql5.com"
#property version   "1.00"
#property strict
//+------------------------------------------------------------------+
//| Script program start function                                    |
//+------------------------------------------------------------------+

#include <arrays/arraystring.mqh>



void OnStart()
{   

//CArrayString Object variable
//sysmbols hold ArrayString 

CArrayString symbols;   

//here, it checks all open orders and check if there is already existing sysmbol
//if not, it add to ArrayString 

int orders = OrdersTotal();

for (int i=0; i < orders; i++)       
{
   if(OrderSelect(i,SELECT_BY_POS)==false)        continue;
   
   if (symbols.SearchLinear(OrderSymbol()) < 0)         
   symbols.Add(OrderSymbol());   

}

// At this time, this symbols object should have list of symbols which has orders.
//https://www.mql5.com/en/docs/standardlibrary/datastructures/carraystring
//
//Methods inherited from class CArray
//Step, Step, Total, Available, Max, IsSorted, SortMode, Clear, Sort

//Sort
//this has sample
//https://www.mql5.com/en/docs/standardlibrary/datastructures/carray/carraysort

//Sort(0) -> Sorting an array is always ascending. 
symbols.Sort(0);

Print("Total Number of Symbols " + IntegerToString(symbols.Total()) );

for (int i=0; i<symbols.Total(); i++)       

    Print(symbols[i]);



}


//+------------------------------------------------------------------+