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HwndSourceHook Delegate

Represents the method that handles Win32 window messages. 

Namespace:  System.Windows.Interop
Assembly:  PresentationCore (in PresentationCore.dll)

public delegate IntPtr HwndSourceHook(
	IntPtr hwnd,
	int msg,
	IntPtr wParam,
	IntPtr lParam,
	ref bool handled
In XAML, you can use delegates but you cannot define your own.


Type: System.IntPtr

The window handle.

Type: System.Int32

The message ID.

Type: System.IntPtr

The message's wParam value.

Type: System.IntPtr

The message's lParam value.

Type: System.Boolean%

A value that indicates whether the message was handled. Set the value to true if the message was handled; otherwise, false.

Return Value

Type: System.IntPtr
The appropriate return value depends on the particular message. See the message documentation details for the Win32 message being handled.

Use the AddHook method to register this handler to receive messages.

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0