Assembly: System.Web (in system.web.dll)
The OnFieldChanged method raises an event signaling that the DataControlField object's state has changed. Changes to the following properties cause this event to be raised: FooterText, HeaderImageUrl, HeaderText, ShowHeader, SortExpression, and Visible. Derived type properties also raise this event when state changes occur. Web server controls such as DetailsView and GridView typically call the DataBind method in response to a field change event.
Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.
The OnFieldChanged method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.Notes to Inheritors: When overriding OnFieldChanged in a derived class, be sure to call the base class's OnFieldChanged method so that registered delegates receive the event.