ForeignKeyConstraint.UpdateRule Eigenschap

public:
 virtual property System::Data::Rule UpdateRule { System::Data::Rule get(); void set(System::Data::Rule value); };

[System.Data.DataSysDescription("ForeignKeyConstraintUpdateRuleDescr")]
public virtual System.Data.Rule UpdateRule { get; set; }

public virtual System.Data.Rule UpdateRule { get; set; }

[<System.Data.DataSysDescription("ForeignKeyConstraintUpdateRuleDescr")>]
member this.UpdateRule : System.Data.Rule with get, set

member this.UpdateRule : System.Data.Rule with get, set

Public Overridable Property UpdateRule As Rule

Waarde van eigenschap

Een van de Rule waarden. De standaardwaarde is Cascade.

Kenmerken

DataSysDescriptionAttribute

Voorbeelden

In het volgende voorbeeld wordt een ForeignKeyConstraint, stelt u verschillende eigenschappen in en voegt u deze toe aan een DataTable object ConstraintCollection.

' The next line goes into the Declarations section of the module:
' SuppliersProducts is a class derived from DataSet.
Private suppliersProducts As SuppliersProducts 

Private Sub CreateConstraint()
   ' Declare parent column and child column variables.
   Dim parentColumn As DataColumn
   Dim childColumn As DataColumn
   Dim fkConstraint As ForeignKeyConstraint

   ' Set parent and child column variables.
   parentColumn = suppliersProducts.Tables("Suppliers").Columns("SupplierID")
   childColumn = suppliersProducts.Tables("Products").Columns("SupplieriD")
   fkConstraint = New ForeignKeyConstraint( _
       "SuppierFKConstraint", parentColumn, childColumn)

   ' Set null values when a value is deleted.
   fkConstraint.DeleteRule = Rule.SetNull
   fkConstraint.UpdateRule = Rule.Cascade
   fkConstraint.AcceptRejectRule = AcceptRejectRule.Cascade

   ' Add the constraint, and set EnforceConstraints to true.
   suppliersProducts.Tables("Suppliers").Constraints.Add(fkConstraint)
   suppliersProducts.EnforceConstraints = True
End Sub

Zie ook

• AcceptRejectRule
• Rule