TextBoxBase.ClearUndo Method ()
Clears information about the most recent operation from the undo buffer of the text box.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
You can use this method to prevent an undo operation from repeating, based on the state of your application.
The following code example uses TextBox, a derived class. It provides Click event handlers for MenuItem objects that perform Cut, Copy, Paste, and Undo operations. This example requires that a TextBox control named textBox1 has been created.
Available since 1.1