Low Level Keyboard Hook problem

[AndyTheAce]

Hi Folks,

I'm currently writting a LLKeyboard hook, my goal is to redirect all inputs just to one window, regardless what other applications are running.
I made it acutall working so my problem is more trivial:

------SNIPPET-------

LRESULT CALLBACK LLHook(int nCode, WPARAM wParam, LPARAM lParam){
	  KBDLLHOOKSTRUCT *pkh = (KBDLLHOOKSTRUCT *) lParam;
	  BOOL bCtrl 	= GetAsyncKeyState(VK_CONTROL)>>((sizeo(SHORT) * 8) - 1);
	  BOOL bShift	= GetAsyncKeyState(VK_SHIFT)>>((sizeof(SHORT) * 8) - 1);
		
	  if (nCode==HC_ACTION) {
		    if(GetFocus() == hWndredirect){
			    if(!bCtrl && !bShift){				
				   PostMessage(GetFocus(),WM_KEYDOWN,pkh->vkCode,pkh->scanCode);
				   //PostMessage(GetFocus(),WM_KEYUP,pkh->vkCode,(LPARAM)0);				
			    }			
		    }
		    else SetFocus(hWndredirect);
	    }
	   return(-1);
}

------SNIPPET-------


This code works well, my only problem is that hWndredirect receives all keys twice. You type "a", "aa" appears and so on, I outcommented the WM_KEYUP message already, without that it was "aaaa".
My guess is that there probably something is wrong with the scanCode but I can't figure out the problem really.

Thanks in Advance, Andy

[golanshahar]

Your problem is that in the hook you don’t distinguish between Down/Up stroke whenever you enter the hook you sending WM_KEYDOWN message first for the down and second for the up.

if (nCode==HC_ACTION)
{
    if(GetFocus() == hWndredirect)
  {
    if(!bCtrl && !bShift)
    {  
      if ( wParam == WM_KEYDOWN) 
        PostMessage(GetFocus(),WM_KEYDOWN,pkh->vkCode,pkh->scanCode);
      else if ( wParam == WM_KEYUP )
        PostMessage(GetFocus(),WM_KEYUP,pkh->vkCode,(LPARAM)0);        
    }      
  }
  else SetFocus(hWndredirect);
}

Just bear in mind that there are other events like WM_SYSKEYDOWN/WM_SYSKEYUP.

Cheers

[AndyTheAce]

Thanks for reply, you were right I forgot to catch that.
But its still not really good... when I pass the scanCode the result
is a senseless number of characters.. but when I pass (LPARAM)0 insteat, it works fine.

Any explanation for that?