Locks the most recent undo unit of the undo stack of the application. This prevents the locked unit from being merged with undo units that are added subsequently.
Namespace: System.Windows.Controls.Primitives Assembly: PresentationFramework (in presentationframework.dll)
Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.