ForeignKeyConstraint Constructor (DataColumn^, DataColumn^)
.NET Framework (current version)
Initializes a new instance of the ForeignKeyConstraint class with the specified parent and child DataColumn objects.
Assembly: System.Data (in System.Data.dll)
Parameters
- parentColumn
-
Type:
System.Data::DataColumn^
The parent DataColumn in the constraint.
- childColumn
-
Type:
System.Data::DataColumn^
The child DataColumn in the constraint.
| Exception | Condition |
|---|---|
| ArgumentNullException | One or both of the columns is null. |
| InvalidConstraintException |
The following example creates a new ForeignKeyConstraint, sets some of its properties, and adds it to a DataTable object's ConstraintCollection.
' The next line goes into the Declarations section. ' 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(parentColumn, childColumn) ' Set various properties of the constraint. With fkConstraint .ConstraintName = "suppierFKConstraint" .DeleteRule = Rule.SetNull .UpdateRule = Rule.Cascade .AcceptRejectRule = AcceptRejectRule.Cascade End With ' Add the constraint, and set EnforceConstraints to true. suppliersProducts.Tables("Products").Constraints.Add(fkConstraint) suppliersProducts.EnforceConstraints = True End Sub
.NET Framework
Available since 1.1
Available since 1.1
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