public NavigationPropertyBindingConfiguration HasRequiredBinding <TTargetType, TDerivedEntityType>( Expression <Func <TDerivedEntityType, TTargetType> > navigationExpression, string entitySetName) where TTargetType : class where TDerivedEntityType : class, TEntityType { if (navigationExpression == null) { throw Error.ArgumentNull("navigationExpression"); } EntityTypeConfiguration <TDerivedEntityType> derivedEntityType = _modelBuilder.Entity <TDerivedEntityType>().DerivesFrom <TEntityType>(); return(_configuration.AddBinding(derivedEntityType.HasRequired(navigationExpression), _modelBuilder.EntitySet <TTargetType>(entitySetName)._configuration)); }