GetAsyncKeyState() won't work properly!

Well, I can't figure it out. I have the array of char from A - Z like this:

char vkBuffer[26] = { // Keys here };

I am just making a simple keylogger, but it's not for a hacking reason. I was just playing with it. Anyhow, where do I keep a loop while my program is running and get all the keys into an EDIT box. I have the loop in the Message Loop, but it doesn't receive the keys in order. If I push S, D, and then F, it appears like this:

DSF

Any help?

GetAsyncKeyState don't wait for the message loop and that might cause some weird behaviour from time to time. I usally but it in a while(true) loop but that wouldn't be good practice if you want to run it in the background