ForeignKeyConstraint.UpdateRule Propiedad

Definición

Espacio de nombres:

System.Data

Ensamblado:

System.Data.Common.dll

Source:

ForeignKeyConstraint.cs

Obtiene o establece la acción que se produce en esta restricción cuando se actualiza una fila.

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

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

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

Public Overridable Property UpdateRule As Rule

Valor de propiedad

Rule

Uno de los valores de Rule. De manera predeterminada, es Cascade.

Ejemplos

En el ejemplo siguiente se crea un ForeignKeyConstraintobjeto , se establecen varias de sus propiedades y se agrega a DataTableConstraintCollection.

' 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

Consulte también

• AcceptRejectRule
• Rule