Undoes the last edit operation in the text box. This method is not supported by MaskedTextBox.
The Undo method is inherited from the base TextBoxBase class. However, MaskedTextBox does not support undo functionality.
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.