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ForeignKeyConstraint.UpdateRule Property

Definition

Gets or sets the action that occurs across this constraint on when a row is updated.

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

Property Value

One of the Rule values. The default is Cascade.

Attributes

Examples

The following example creates a ForeignKeyConstraint, sets various of its properties, and adds it to a DataTable object's ConstraintCollection.

VB
' 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

Applies to

Termék Verziók
.NET Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1

See also