Initializes a new instance of the ForeignKeyConstraint class with the specified name, and arrays of parent and child DataColumn objects.
[Visual Basic] Overloads Public Sub New( _ ByVal constraintName As String, _ ByVal parentColumns() As DataColumn, _ ByVal childColumns() As DataColumn _ ) [C#] public ForeignKeyConstraint( string constraintName, DataColumn[] parentColumns, DataColumn[] childColumns ); [C++] public: ForeignKeyConstraint( String* constraintName, DataColumn* parentColumns[], DataColumn* childColumns[] ); [JScript] public function ForeignKeyConstraint( constraintName : String, parentColumns : DataColumn[], childColumns : DataColumn[] );
Exception Type | Condition |
---|---|
ArgumentNullException | One or both of the columns is a null reference (Nothing). |
InvalidConstraintException | The columns have different data types.
-Or- The tables don't belong to the same DataSet. |
[Visual Basic]
' The next line goes into the Declarations section of the module: ' SuppliersProducts is a class derived from DataSet. Private myDataSet As SuppliersProducts Private Sub CreateConstraint() ' Declare parent column and child column variables. Dim pCols(1) As DataColumn Dim cCols(1) As DataColumn Dim myFKC As ForeignKeyConstraint ' Set parent and child column variables. pCols(0) = MyDataSet.Tables("OrderDetails").Columns("OrderID") pCols(1) = MyDataSet.Tables("OrderDetails").Columns("ProductID") cCols(0) = MyDataSet.Tables("Sales").Columns("OrderID") cCols(1) = MyDataSet.Tables("Sales").Columns("ProductID") myFKC = New ForeignKeyConstraint("ProductSalesOrders", pCols, cCols) ' Set various properties of the constraint. With myFKC .DeleteRule = Rule.SetDefault .UpdateRule = Rule.Cascade .AcceptRejectRule = AcceptRejectRule.Cascade End With ' Add the constraint, and set EnforceConstraints to true. myDataSet.Tables("OrderDetails").Constraints.Add myFKC myDataSet.EnforceConstraints = True End Sub
ForeignKeyConstraint Class | ForeignKeyConstraint Members | System.Data Namespace | ForeignKeyConstraint Constructor Overload List