The framework calls this member function to inform the parent window of a control that an event has occurred in the control or that the control requires some kind of information.


      virtual BOOL OnNotify( 
   WPARAM wParam, 
   LPARAM lParam, 
   LRESULT* pResult  


  • wParam
    Identifies the control that sends the message if the message is from a control. Otherwise, wParam is 0.

  • lParam
    Pointer to a notification message (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.

  • pResult
    Pointer to an LRESULT variable in which to store the result code if the message is handled.

Return Value

An application returns nonzero if it processes this message; otherwise 0.


OnNotify processes the message map for control notification.

Override this member function in your derived class to handle the WM_NOTIFY message. An override will not process the message map unless the base class OnNotify is called.

For more information on the WM_NOTIFY message, see Technical Note 61 (TN061), ON_NOTIFY and WM_NOTIFY messages. You may also be interested the related topics described in Control Topics, and TN062, Message Reflection for Windows Controls.


Header: afxwin.h

See Also

CWnd Class
Hierarchy Chart