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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


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.

.NET Framework

Supported in: 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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