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NullExtension Class

Implements a XAML markup extension in order to return a null object, which you can use to explicitly set values to Nothing.

Namespace:  System.Windows.Markup
Assembly:  PresentationFramework (in PresentationFramework.dll)

<MarkupExtensionReturnTypeAttribute(GetType(Object))> _
Public Class NullExtension _
	Inherits MarkupExtension
Dim instance As NullExtension
For XAML information, see x:Null Markup Extension.

This class is a markup extension implementation. Markup extension classes exist mainly to provide infrastructure support for how WPF XAML processors interpret a particular extension. The members that markup extension implementation classes expose are not typically intended to be called from your code. This markup extension class supports the x:Null Markup Extension usage for XAML.

When you set a dependency property value to Nothing, you are not necessarily setting the property to its default value. The default value of a dependency property depends on its dependency property registration. For more information, see ClearValue.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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