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DataControlField.OnFieldChanged Method

Definition

Raises the FieldChanged event.

protected:
 virtual void OnFieldChanged();
protected virtual void OnFieldChanged ();
abstract member OnFieldChanged : unit -> unit
override this.OnFieldChanged : unit -> unit
Protected Overridable Sub OnFieldChanged ()

Remarks

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 Handling and Raising Events.

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.

Applies to