MQL4 Reference Constants, Enumerations and Structures Data Structures

Data Structures

MQL4 Language offers 8 predefined structures:


What's new in MQL5

The fifth generation platform features the significantly expanded trading functionality. It allows working with ticks and the Depth of Market. Order and trade request properties have been expanded as well. The platform has the ability to handle trading events. The economic calendar functions have also been added. The new data storage structures are meant for passing and handling these huge amounts of data:

  • MqlParam describes inputs when creating the IndicatorCreate() function;
  • MqlRates provides info on historical data containing price, volume and spread;
  • MqlBookInfo gets data from the Depth of Market (quotes window);
  • MqlTick is designed for obtaining the most needed data on the current prices in a timely manner;
  • MqlTradeRequest is used for sending trade requests;
  • MqlTradeCheckResult contains results of checking a trade request before it was sent;
  • MqlTradeResult returns the trade server response to a trade request;
  • MqlTradeTransaction provides a description of an obtained transaction;
  • Economic calendar structures are used to obtain news and relevant macro economic indices sent directly to the platform.