Indicates that the user pressed the F1 key. If a menu is active when F1 is pressed, WM_HELP is sent to the window associated with the menu; otherwise, WM_HELP is sent to the window that has the keyboard focus. If no window has the keyboard focus, WM_HELP is sent to the currently active window.
Must be zero.
The address of a HELPINFO structure that contains information about the menu item, control, dialog box, or window for which Help is requested.
The DefWindowProc function passes WM_HELP to the parent window of a child window or to the owner of a top-level window.
Minimum supported client
|Windows XP [desktop apps only]|
Minimum supported server
|Windows 2000 Server [desktop apps only]|