Retrieves the System.Web.UI.IDataSource interface that the data-bound control is associated with, if any.
An System.Web.UI.IDataSource that represents the data source identified by DataBoundControl.DataSourceID.
The DataBoundControl.GetData method calls the DataBoundControl.GetDataSource method internally. A valid System.Web.UI.IDataSource instance is retrieved by these two methods and is cached by the System.Web.UI.WebControls.DataBoundControl object until the DataBoundControl.OnDataPropertyChanged method signals that the data source has changed.