A thread that needs to receive character input from the user must include the TranslateMessage function in its message loop. This function examines the virtual-key code of a keystroke message and, if the code corresponds to a character, places a character message into the message queue. The character message is removed and dispatched on the next iteration of the message loop—the wParam parameter of the message contains the character code.
In general, a thread's message loop should use the TranslateMessage function to translate every message, not just virtual-key messages. Although TranslateMessage has no effect on other types of messages, it guarantees that keyboard input is translated correctly. The following code fragment shows how to include the TranslateMessage function in a typical thread message loop:
while (GetMessage(&msg, (HWND) NULL, 0, 0)) {
if (TranslateAccelerator(hwndMain, haccl, &msg) == 0) {
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}