Assembly: System.Web (in System.Web.dll)
The ListSourceHelper class, which is used for the DataSourceControl class's IListSource implementation, checks the method for both the IListSource.ContainsListCollection and IListSource.GetList calls to determine whether the data source control is associated with one or more data source views. If returns a null reference (Nothing in Visual Basic), which is the default implementation of the method, IListSource.ContainsListCollection returns false and IListSource.GetList returns a null reference (Nothing in Visual Basic).
The following code example demonstrates how a class that extends the DataSourceControl class can override the default implementation, which returns a null reference (Nothing in Visual Basic), to provide a collection of view names. The CsvDataSource class only supports one view; therefore, a collection of one element with the default view name is returned. This code example is part of a larger example provided for the DataSourceControl class.