SpreadInfo

//+------------------------------------------------------------------+
//|                                                   SpreadInfo.mq4 |
//|                        Copyright 2014, MetaQuotes Software Corp. |
//|                                              http://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "Copyright 2014, MetaQuotes Software Corp."
#property link      "http://www.mql5.com"
#property version   "1.00"
#property strict
//+------------------------------------------------------------------+
//| Global Variables                                                 |
//+------------------------------------------------------------------+
double Spread;
//+------------------------------------------------------------------+
//| Expert initialization function                                   |
//+------------------------------------------------------------------+
int OnInit()
  {
//---
   return(INIT_SUCCEEDED);
  }
//+------------------------------------------------------------------+
//| Expert deinitialization function                                 |
//+------------------------------------------------------------------+
void OnDeinit(const int reason)
  {
//---
  }
//+------------------------------------------------------------------+
//| Expert tick function                                             |
//+------------------------------------------------------------------+
void OnTick()
  {
//---
   Spread = MarketInfo(Symbol(), MODE_ASK) - MarketInfo(Symbol(), MODE_BID);
   Comment("Spread: " + DoubleToStr(Spread, Digits));
  }
//+------------------------------------------------------------------+