Thread: GetAsyncKeyState - if or while?

Hey fellas, I just found out that this nifty little command would help me capture the ALT key in my program. Question is, how exactly do I use this command to capture the key?

Lemme know if this makes sense:

if (GetAsyncKeyState(VK_ALT))
//do whatever

Because, I'm thinking that I will have to setup a loop to actually catch the ALT keypress. Won't I? I mean it's not like getch() that will wait on the user to enter something. Something to the effect of:

while (GetAsyncKeyState(VK_ALT))
//do whatever

Won't I? Or am I just typing nonsense here?

MSDN doesn't show me any examples of it's usage in C. Thanks in advance.

well whenever you test for input? test for alt of in the main program loop somewhere with the if form?

If you have windows proggie then capure WM_KEYDOWN and look for the proper Virtual code (I think its VK_MENU...but i may be wrong)...

If you have a console then the way I prefer to do it is to setup a seperate thread to read the keyboard using ReadConsoleInput().....

I did know about the VK_MENU. You're quite right.

My mind slipped me when I wrote VK_ALT, nonsense I tell you.

I'm going to attempt the ReadConsoleInput. Is that also in Windows.h?

Originally posted by johnnyd

I'm going to attempt the ReadConsoleInput. Is that also in Windows.h?

Yup its a standard Windows function.......

I've seen some peeps use GetKeyState(VK_MENU & 0x8000) in their C code. What's the significance of the & 0x8000?

>What's the significance of the & 0x8000?
That determines if the most signifigant bit is set.

-Prelude