public static CriteriaOperator GetCriteria(this CollectionSourceBase collectionSource) { var externalCriteria = collectionSource.GetExternalCriteria(); var associatedCollectionCriteria = collectionSource.GetAssociatedCollectionCriteria(); return((CriteriaOperator)typeof(CollectionSourceBase).CallMethod("CombineCriteria", new object[] { new[] { associatedCollectionCriteria, externalCriteria } })); }