The WM_NOTIFY message informs the parent window of a control that an event has occurred in the control or that the control requires some kind of information.
WM_NOTIFY
idCtrl = (int) wParam;
pnmh = (LPNMHDR) lParam;
Parameters
idCtrl
Identifier of the control sending the message. This identifier is not guaranteed to be unique. An application should use the hwindFrom or idFrom member of the NMHDR structure (passed as the lParam parameter) to identify the control.
pnmh
Pointer to an NMHDR structure that contains the notification code and additional information. For some notification messages, this parameter points to a larger structure that has the NMHDR structure as its first member.
Return Values
The return value is ignored except for notification messages that specify otherwise.
See Also