detect focus

[MPrestonf12]

case WM_COMMAND:
		switch(wParam)
		{
		case EN_SETFOCUS:
			MessageBox(NULL,"Edit box has focus", "Focus",MB_OK);
		}

I am trying to detect when my editbox has gained focus. Im not sure about the switch statement. Also what is a HIWORD and LOWORD? Thanks

[HarryW]

What are you not sure about with the switch statements?

HIWORD is the high WORD of a double word (DWORD) type. WORD is 16 bits, and DWORD is 32-bits. If you imagine it in binary, the high word is the left 16 bits, and the low word is the right 16 bits.

[Vlatko]

Is the code working? Here is info on the EN_SETFOCUS message

EN_SETFOCUS
The EN_SETFOCUS notification message is sent when an edit control receives the keyboard focus. The parent window of the edit control receives this notification message through the WM_COMMAND message. 

EN_SETFOCUS 
idEditCtrl = (int) LOWORD(wParam); // identifier of edit control 
wNotifyCode = HIWORD(wParam);      // notification code 
hwndEditCtrl = (HWND) lParam;      // handle of edit control

[MPrestonf12]

no the code doesn't work. Im not sure about the first part of the switch statement

switch(wParam)

What should go where wParam is? Right now when I click in the edit box nothing happens.

[HarryW]

I think it's meant to be HIWORD(wParam)