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DefWindowProc Reference in C#, VB.NET and VB6


Visual Basic 6 definition
Declare Function DefWindowProc Lib "user32.dll" Alias "DefWindowProcA" (ByVal hWnd As Long, ByVal Msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long

Visual Basic .NET definition
Declare Function DefWindowProc Lib "user32" Alias "DefWindowProcA" (ByVal hwnd As Integer, ByVal wMsg As Integer, ByVal wParam As Integer, ByVal lParam As Integer) As Integer

C# definition
[DllImport("user32", EntryPoint="DefWindowProc")] public static extern int DefWindowProcA(int hwnd, int wMsg, int wParam, int lParam)


DefWindowProc explicitly calls the operating system's default window procedure to process a message for a window. This default window procedure provides the minimal functionality necessary for a window procedure function and should be used to provide the default implementation of window messages. DefWindowProc Calls the default window procedure to provide default processing for any window messages that an application does not process. Any of the following:System.Windows.Forms.Form.DefWndProcSystem.Windows.Forms.Control.DefWndProcSystem.Windows.Forms.NativeWindow.DefWndProc

Return Value

The function returns the return value of whatever message was processed.


Further Information:

For further information on Windows API functions such as these, and how to use these API's in your C# and VB.NET applications, please refer to the book 'Network programming in .NET' (Buy at Amazon UK) (Buy at Amazon US)

Visual Basic 6 example source code

C# example source code

Provide a code example



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