trigger a key press event?

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How can I program triggering a key press/event?

For the following use case: Normally one can zoom with the "+" and "-" keys, but I would like to zoom with "q" and "r" and my idea is when "q" is pressed to trigger pressing the "+" key. Or are there better ideas how to create this use case?

 
Do you know that you can click and drag the date/time axis. Right to zoom in, left to zoom out.
 

I found it:


#import "user32.dll"

void keybd_event(int bVk,int bScan,int dwFlags,int dwExtraInfo);

keybd_event(187,0,0,0); //+ button

keybd_event(189,0,0,0); //- button

Keycodes: http://help.adobe.com/en_US/AS2LCR/Flash_10.0/help.html?content=00000520.html
 
OnChartEvent() function  with CHARTEVENT_KEYDOWN is to survey the keyboard.
 
Nikolay:

I found it:


#import "user32.dll"

void keybd_event(int bVk,int bScan,int dwFlags,int dwExtraInfo);

keybd_event(187,0,0,0); //+ button

keybd_event(189,0,0,0); //- button

Keycodes: http://help.adobe.com/en_US/AS2LCR/Flash_10.0/help.html?content=00000520.html


I am trying to make a custom indicator and want some thing like.

if(CTRL + Q) {

Alert("Hello World")

}

how would you code this?

The return value of the keybd_event is void so not sure how to do.

 
Same question posted 16 minutes earlier.
mql4 pressing two keyboard buttons at the same time
mql4 pressing two keyboard buttons at the same time
  • www.mql5.com
Hi all I want to make a custom indicator which detects the pressing down of multiple keys...
 
whroeder1:
Same question posted 16 minutes earlier.


Ok so I worked out what that those lines of code do. 

keybd_event(187,0,0,0); //+ button

means press + button. But how does mql4 detect multiple key presses? CHARTEVENT_KEYDOWN only takes one sparam argument.

 
traderbigbear92: But how does mql4 detect multiple key presses? CHARTEVENT_KEYDOWN only takes one sparam argument.
It doesn't like every other Windows program. Key (e.g. Alt) down - remember, key down - process key modified by (e.g. Alt.)
 
Nikolay:

I found it:


#import "user32.dll"

void keybd_event(int bVk,int bScan,int dwFlags,int dwExtraInfo);

keybd_event(187,0,0,0); //  NOT + button, but =+ button

keybd_event(189,0,0,0); //  NOT - button, but -_ button

//----

keybd_event(107,0,0,0); //  107 the + code numbers keyboard

keybd_event(109,0,0,0); //  109 the - code numbers keyboard


//-- for Q and R

keybd_event(81,0,0,0); //  81 the Q code numbers keyboard

keybd_event(82,0,0,0); //  82 the R code numbers keyboard


//---

// I use this code on my indicator like code below
// and working smoothly, no problems.

#include <WinUser32.mqh>

#define KEY_PLUS   107
#define KEY_MINUS  109

void OnChartEvent(const int id,            // Event identifier
                  const long &lparam,      // Event parameter of long type
                  const double &dparam,    // Event parameter of double type
                  const string &sparam)    // Event parameter of string type
  {
//---
   ResetLastError();
   RefreshRates();
   //--
   static bool keyPressed=false;

//--- this is an Event of a keystroke
   if(id==CHARTEVENT_KEYDOWN)
     {
      if(lparam==KEY_PLUS || lparam==KEY_MINUS)
        {
         if(!keyPressed) keyPressed=true;
         else keyPressed=false;
        }
      //--
      switch(int(lparam)) 
        { 
          case KEY_PLUS:  
                 {
                    .... etc
                 }
               break;

          case KEY_MINUS: 
                 {
                    .... etc
                 }
               break;
        }

     }
  }
//--------------------------------------------//


  
static datetime lastctrl=0;
void OnChartEvent(const int id, const long& lparam, const double& dparam, const string& sparam)
{
   if(id==CHARTEVENT_KEYDOWN)
   {
      Print("lparam:"+lparam+" dparam:"+dparam+" sparam:"+sparam);
      if(lparam==17)
         lastctrl=TimeCurrent();
      if(TimeCurrent()-lastctrl<2)
      {
         if (lparam == 49)
            OpenBuy();
         if (lparam == 51)
            OpenSell();
         if (lparam == 48)
            CloseAll();
      }
   }
}
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