SendMessage, When To Use KEYDOWN, SYSKEYDOWN, etc?

Question

I am writing an application that sends keystrokes to another application using SendMessage.

[DllImport(\"user32.dll\")]
public static extern in         


        

Answer 1

Microsoft explains the difference between these WM messages here Keyboard Input (Windows).

WM_SYSKEYDOWN simulates system commands like ALT + TAB used to switch windows.

WM_CHAR simulates user input like input in a text box for instance.

WM_KEYDOWN is usually used together with WM_KEYUP. See WM_KEYDOWN message (Windows).

Most probably you will want to use WM_CHAR.