ForeignKeyConstraint Class   System.Data Namespace

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Indicates what kind of action should take place across this constraint when AcceptChanges is invoked.

[ VB ]
Overridable Public Property AcceptRejectRule As AcceptRejectRule

[ C# ]
public AcceptRejectRule AcceptRejectRule {virtual get; virtual
   set;}

[ C++ ]
public: __property virtual AcceptRejectRule get_AcceptRejectRule ( );
public: __property virtual void set_AcceptRejectRule ( AcceptRejectRule );

[ JScript ]
public function get AcceptRejectRule ( ) : AcceptRejectRule;
public function set AcceptRejectRule ( AcceptRejectRule );

One of the AcceptRejectRule values. Possible values include None, Cascade, and Default.

Changes to a DataRow or DataTable are not final until the Accept method is invoked. At that point, the AcceptRejectRule will determine the course of action on any values that have been changed or deleted.

The following example initializes a ForeignKeyConstraint, sets its AcceptRejectRule, and adds the constraint to a DataTable object's ConstraintsCollection.

[ VB ] 
' 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 pCol As DataColumn
   Dim cCol As DataColumn
   Dim myFKC As ForeignKeyConstraint
   ' set parent and child column variables.
   pCol = myDataSet.Tables ( "Suppliers ).Columns ( "SupplierID" )
   cCol = myDataSet.Tables ( "Products" ).Columns ( "SupplieriD" )
   myFKC = New ForeignKeyConstraint ( "SuppierFKConstraint", pCol, cCol )
   ' set null values when a value is deleted.
   myFKC.DeleteRule = Rule.SetNull
   myFKC.UpdateRule = Rule.Cascade
   myFKC.AcceptRejectRule = AcceptRejectRule.Cascade
   ' add the constraint, and set EnforceConstraints to true.
   myDataSet.Tables ( "Suppliers" ).Constraints.Add myFKC
   myDataSet.EnforceConstraints = True
End Sub

ForeignKeyConstraint Members   AcceptRejectRule

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