Implements a XAML markup extension in order to return a null object, which you can use to explicitly set values to null.
Assembly: PresentationFramework (in PresentationFramework.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml
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 null, 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.
Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003