When overridden in a derived class, verifies that the object a data-bound control binds to is one it can work with.
Assembly: System.Web (in System.Web.dll)
The method is only called in the BaseDataBoundControl class's mutator (setter) for the DataSource property. Derived classes implement the method to check the type of the object that is set for the DataSource property, to ensure that the data-bound control can work with the type. If the type is not recognized, derived type implementations throw an exception.