Question

im using keybd_event(); and i want use SendMessage(); to send keystroke to notepad, can this be done?

Answer 1

using SendMessage to insert text into the edit buffer (which it sounds like you want):

HWND notepad = FindWindow(_T("Notepad"), NULL);
HWND edit = FindWindowEx(notepad, NULL, _T("Edit"), NULL);
SendMessage(edit, WM_SETTEXT, NULL, (LPARAM)_T("hello"));

if you need keycodes and arbitrary keystrokes, you can use SendInput() (available in 2k/xp and preferred), or keybd_event()` (which will end up calling SendInput in newer OSs) some examples here:

http://www.codeguru.com/forum/showthread.php?t=377393

there’s also WM_SYSCOMMAND/WM_KEYDOWN/WM_KEYUP/WM_CHAR events for SendMessage which you might be interested in.