Gets the ForeignKeyConstraint for the relation.
[Visual Basic] Overridable Public ReadOnly Property ChildKeyConstraint As _ ForeignKeyConstraint [C#] public ForeignKeyConstraint ChildKeyConstraint {virtual get;} [C++] public: __property virtual ForeignKeyConstraint* get_ChildKeyConstraint(); [JScript] public function get ChildKeyConstraint() : ForeignKeyConstraint;
The following example create a new ForeignKeyConstraint and assigns it to the ChildKeyConstraint property.
[Visual Basic]
Private Sub SetChildKeyConstraint() Dim dr As DataRelation Dim cCol As DataColumn Dim pCol As DataColumn ' Set child and parent columns. pCol = DataSet1.Tables("Suppliers").Columns("SupplierID") cCol = DataSet1.Tables("Products").Columns("SupplierID") dr = New DataRelation("SuppliersConstraint", pCol, cCol) ' Create ForeignKeyConstraint using the function below. Dim fk As ForeignKeyConstraint fk = CreateConstraint(pCol, cCol) ' Assign the constraint to the ChildKeyConstraint property dr.ChildKeyConstraint = fk End Sub Private Function CreateConstraint(pCol As DataColumn, cCol As DataColumn) _ As ForeignKeyConstraint Dim myFKC As ForeignKeyConstraint myFKC = New ForeignKeyConstraint(pCol, cCol) ' Set null values when a value is deleted. myFKC.DeleteRule = Rule.SetNull myFKC.UpdateRule = Rule.Cascade myFKC.AcceptRejectRule = AcceptRejectRule.Cascade CreateConstraint = myFKC End Function
DataRelation Class | DataRelation Members | System.Data Namespace | AcceptRejectRule | ParentKeyConstraint | Rule