An example of where this interface might be implemented is default and cancel button processing. Default buttons are notified when an unprocessed ENTER key is entered for a form, just like a dialog box would be closed. Similarly, cancel buttons are notified whenever an unprocessed ESC key is entered on a form, much like a dialog box would be dismissed.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
Assembly Versions: 1.0.5000.0, 2.0.0.0