Sent immediately before the IME generates the composition string as a result of a keystroke. A window receives this message through its WindowProc function.
LRESULT CALLBACK WindowProc( HWND hwnd, WM_IME_STARTCOMPOSITION, WPARAM wParam, LPARAM lParam );
This message has no parameters.
This message has no return value.
This message is a notification to an IME window to open its composition window. An application should process this message if it displays composition characters itself.
If an application has created an IME window, it should pass this message to that window. The DefWindowProc function processes the message by passing it to the default IME window.
|Minimum supported client
||Windows 2000 Professional [desktop apps only]
|Minimum supported server
||Windows 2000 Server [desktop apps only]