This static function implements the window procedure.
static LRESULT CALLBACK WindowProc( 
   HWND hWnd, 
   UINT uMsg, 
   WPARAM wParam, 
   LPARAM lParam  
);
Parameters
hWnd
[in] The handle to the window.uMsg
[in] The message sent to the window.wParam
[in] Additional message-specific information.lParam
[in] Additional message-specific information.
Return Value
The result of the message processing.
Remarks
WindowProc uses the default message map (declared with BEGIN_MSG_MAP) to direct messages to the appropriate handlers. If necessary, WindowProc calls DefWindowProc for additional message processing. If the final message is not handled, WindowProc does the following:
Performs unsubclassing if the window was unsubclassed.
Clears m_hWnd.
Calls OnFinalMessage before the window is destroyed.
You can override WindowProc to provide a different mechanism for handling messages.
Requirements
Header: atlwin.h