Defines the prototype for the callback function used by RemoveWindowSubclass and SetWindowSubclass.

Syntax

typedef LRESULT (CALLBACK *SUBCLASSPROC)(      
    HWND hWnd,
    UINT uMsg,
    WPARAM wParam,
    LPARAM lParam,
    UINT_PTR uIdSubclass,
    DWORD_PTR dwRefData
);

Parameters

hWnd

The handle to the subclassed window.

uMsg

The message being passed.

wParam

Additional message information. The contents of this parameter depend on the value of uMsg.

lParam

Additional message information. The contents of this parameter depend on the value of uMsg.

uIdSubclass

The subclass ID.

dwRefData

The reference data provided to the SetWindowSubclass function. This can be used to associate the subclass instance with a "this" pointer.

Return Value

The return value is the result of the message processing and depends on the message sent.

Prototype Information

Minimum DLL Version	comctl32.dll version 5.8 or later
Custom Implementation	No
Header	commctrl.h
Import library	user-defined
Minimum operating systems	Windows XP