Source Control. IData Source. Data Source Changed Event
Occurs when a data source control has changed in a way that affects data-bound controls.
event EventHandler System.Web.UI.IDataSource.DataSourceChanged;
Custom Event DataSourceChanged As EventHandler Implements System.Web.UI.IDataSource
This event is raised when the underlying data source has changed. The change may be due to a change in the control's properties or a change in the data due to an edit action performed by the DataSourceControl.