The DefWindowProc function calls the default window procedure to provide default processing for any window messages that an application does not process. This function ensures that every message is processed. DefWindowProc is called with the same parameters received by the window procedure.

Syntax

LRESULT DefWindowProc(      
    HWND hWnd,
    UINT Msg,
    WPARAM wParam,
    LPARAM lParam
);

Parameters

hWnd

[in] Handle to the window procedure that received the message.

Msg

[in] Specifies the message.

wParam

[in] Specifies additional message information. The content of this parameter depends on the value of the Msg parameter.

lParam

[in] Specifies additional message information. The content of this parameter depends on the value of the Msg parameter.

Return Value

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

Remarks

Windows 95/98/Me: DefWindowProcW is supported by the Microsoft Layer for Unicode (MSLU). To use this, you must add certain files to your application, as outlined in Microsoft Layer for Unicode on Windows 95/98/Me Systems.

Example

For an example, see Designing a Window Procedure.

Function Information

Minimum DLL Version	user32.dll
Header	Declared in Winuser.h, include Windows.h
Import library	User32.lib
Minimum operating systems	Windows 95, Windows NT 3.1
Unicode	Implemented as ANSI and Unicode versions.

See Also

Window Procedures Overview, CallWindowProc, DefDlgProc, WindowProc