Check for Market Open Hours - bibliothèque pour MetaTrader 5

The MarketOpenHours.mqh file checks the Market Open Hours against the server time at the broker. Its input is only the Symbol name as string type. As a result you get a bool, true - the market is open, false - the market is closed. In the following image i show the Open Hours of my broker DarwinEx for the symbol EURUSD.

You can see how different these open times are on different weekdays. So here is your include file:

//+------------------------------------------------------------------+
//|                                              MarketOpenHours.mqh |
//|                                        Wolfgang Melz, wm1@gmx.de |
//|                                                 https://melz.one |
//+------------------------------------------------------------------+
#property copyright "Wolfgang Melz, wm1@gmx.de"
#property link      "https://melz.one"

//+------------------------------------------------------------------+
//| MarketOpenHours                                                  |
//+------------------------------------------------------------------+
bool MarketOpenHours(string sym) {
  bool isOpen = false;                                  // by default market is closed
  MqlDateTime mdtServerTime;                            // declare server time structure variable
  datetime dtServerDateTime = TimeTradeServer();        // store server time 
  if(!TimeToStruct(dtServerDateTime,                    // is servertime correctly converted to struct?
                   mdtServerTime)) {
    return(false);                                      // no, return market is closed
  }

  ENUM_DAY_OF_WEEK today = (ENUM_DAY_OF_WEEK)           // get actual day and cast to enum
                            mdtServerTime.day_of_week;

  if(today > 0 || today < 6) {                          // is today in monday to friday?
    datetime dtF;                                       // store trading session begin and end time
    datetime dtT;                                       // date component is 1970.01.01 (0)
    datetime dtServerTime = dtServerDateTime % 86400;   // set date to 1970.01.01 (0)
    if(!SymbolInfoSessionTrade(sym, today,              // do we have values for dtFrom and dtTo?
                               0, dtF, dtT)) {
      return(false);                                    // no, return market is closed
    }
    switch(today) {                                     // check for different trading sessions
      case 1:
        if(dtServerTime >= dtF && dtServerTime <= dtT)  // is server time in 00:05 (300) - 00:00 (86400)
          isOpen = true;                                // yes, set market is open
        break;
      case 5:
        if(dtServerTime >= dtF && dtServerTime <= dtT)  // is server time in 00:04 (240) - 23:55 (86100)
          isOpen = true;                                // yes, set market is open
        break;
      default:
        if(dtServerTime >= dtF && dtServerTime <= dtT)  // is server time in 00:04 (240) - 00:00 (86400)
          isOpen = true;                                // yes, set market is open
        break;
    }
  }
  return(isOpen);
}

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

The first part checks for the weekday, Mon - Fri to allow opening trades and trailing stop during the week. In the switch command the actual server time is checked against the broker's symbol session.

Implications:

• If you run this script on every tick or every minute, it will give the exact open hours according to the broker's server like you see in the above image.
• If you run this script every 5 minutes on my broker account, it is correct only on Monday 00:05 - 00:00
• If you run this script on the open of each new bar, the first bar of every weekday get false, market closed also for the last bar on Friday
• If you run this script on PERIOD_D1, PERIOD_W1, PERIOD_MN1 it will not give a true signal for my broker because it runs at 00:00 and market open is at 00:04