Sample implementation: How to send trading signals from Metatrader to Telegram channel/group/private chat with Telegram4MQL

Signal2Channel.mq4

//+------------------------------------------------------------------+
//|                                               Signal2Channel.mq4 |
//|                                                   steven england |
//|                         https://Telegram4MQL.steven-england.info |
//+------------------------------------------------------------------+
#property copyright "steven england"
#property link      "https://Telegram4MQL.steven-england.info"
#property version   "1.00"

#import "Telegram4Mql.dll"
   string TelegramSendTextAsync(string ApiKey, string ChatId, string ChatText);
   string TelegramSendText(string ApiKey, string ChatId, string ChatText);
#import
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//|                                                                  |
//+------------------------------------------------------------------+
void OnInit()
{
   sample();
}
void sample() // this entry point is only for testing
{
   // Your config parameters here
   // The api key of your telegram bot:
   string apikey = "<YOUR API KEY>";
   // The chat ID of your channel you want to post to:
   string chatid = "<YOUR CHAT ID>";
   
   /* Your incredible Expert Advisor logic here
      ...
      Some (not meaningful) example values:
   */
   int      cmd = OP_SELL;        // operation
   double   volume = 0.1;         // volume
   double   price = 0.1;          // price
   int      slippage = 1;         // slippage
   double   stoploss = 0.1;       // stop loss
   double   takeprofit = 0.1;     // take profit
   string   comment = "a comment";// comment
   int      magic = 0;            // magic number
   datetime expiration = 0;       // pending order expiration
   color    arrow_color = clrRed; // color
   
   // Ready to send an order
   string text2send = "";
   int ordersend = OrderSend(Symbol(), cmd, volume, price, slippage, stoploss, takeprofit, comment, magic, expiration, arrow_color);
   
   if(ordersend < 0)
   {
      HandleSendError(GetLastError()); // implement this custom functon on your own.
      return;
   }
   
   // Describe your order for the others
   if(OrderSelect(ordersend, SELECT_BY_TICKET, MODE_TRADES) == true)
   {
      text2send = "MyIncredibleSignal\n" +       
      "Symbol: " + Symbol() + "\n" +       
      "Type: " + OrderType() + "\n" +       
      "Open Time: " + OrderOpenTime() + "\n" +      
      "Open Price: " + OrderOpenPrice() + "\n";
      //
   }
   else
   {
      HandleSelectError(GetLastError()); // implement this custom functon on your own.
      return;
   }
  
   // Send a text message to a channel either blocking or non blocking
   
   // Non blocking if Expert Advisor must immediatly return -> you cannot say if the message was really sent
   TelegramSendTextAsync(apikey, chatid, text2send);
   // Blocking if your Expert Advisor must not immediatly return -> you can check if sending was successful
   string telegramresult = TelegramSendText(apikey, chatid, text2send);
   if (telegramresult != "0")
   {
      HandleTelegramError(telegramresult); // implement this custom functon on your own.
   }
}