System.Web 2.0.0.0 System.Delegate `` `` System.Void To be added. To be added.

The event is raised when a control attempts to change between edit, insert, and read-only mode, but before the mode actually changes. This allows you to provide an event handler that performs a custom routine, such as configuring the control for a specific mode or canceling the mode change, whenever this event occurs.

When you create a delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event-handler delegates, see Events and Delegates.

Represents the method that handles the event of a control.