Dear Mr. Rosh, a new question

[[删除]]

Dear Mr. Rosh

Now I can operate a multi Symbol() ea

I have a question:

If the ea is operating,I change some parameters and compile it

What happen ?

Can the ea run with new parameters I do not remove the ea and rebuild it ?

[Rashid Umarov]

Run this EA on the EURUSD (for example) Daily:

//+------------------------------------------------------------------+
//|                                           Run_And_Compile_EA.mq4 |
//|                      Copyright © 2007, MetaQuotes Software Corp. |
//|                                        https://www.metaquotes.net/ru/ |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2007, MetaQuotes Software Corp."
#property link      "https://www.metaquotes.net/ru/"
 
//---- input parameters
extern int       ExtParam1=1;
extern double    ExtParam2=25.0;
//+------------------------------------------------------------------+
//| expert start function                                            |
//+------------------------------------------------------------------+
int start()
  {
//----
   Print("ExtParam1=",ExtParam1,"   ExtParam2=",ExtParam2);   
//----
   return(0);
  }
//+------------------------------------------------------------------+

then modify values of inputs and compile EA as shown




You'll see like this picture




See also https://docs.mql4.com/cn/check/UninitializeReason

[[删除]]

Dear Mr. Rosh

I understood,I can change some parameters when ea is running

and the ea can run with the new parmetres.

So clever MT4 it is !