Add Method (String, DataColumn, DataColumn)

ConstraintCollection.Add Method (String, DataColumn, DataColumn)

 

Constructs a new ForeignKeyConstraint with the specified name, parent column, and child column, and adds the constraint to the collection.

Namespace:   System.Data
Assembly:  System.Data (in System.Data.dll)

Public Function Add (
	name As String,
	primaryKeyColumn As DataColumn,
	foreignKeyColumn As DataColumn
) As Constraint

Parameters

name
Type: System.String

The name of the ForeignKeyConstraint.

primaryKeyColumn
Type: System.Data.DataColumn

The primary key, or parent, DataColumn.

foreignKeyColumn
Type: System.Data.DataColumn

The foreign key, or child, DataColumn.

Return Value

Type: System.Data.Constraint

A new ForeignKeyConstraint.

The CollectionChanged event occurs if the constraint is added successfully.

The following example adds a new ForeignKeyConstraint to the ConstraintCollection of a DataTable.

Private Sub AddForeignConstraint(dataSet As DataSet)
    Try
        Dim parentColumn As DataColumn = _
            dataSet.Tables("Suppliers").Columns("SupplierID")
        Dim childColumn As DataColumn = _
            dataSet.Tables("Products").Columns("SupplierID")
        dataSet.Tables("Products").Constraints.Add _
            ("ProductsSuppliers", parentColumn, childColumn)

    Catch ex As Exception
        ' In case the constraint already exists, 
        ' catch the collision here and respond.
        Console.WriteLine("Exception of type {0} occurred.", _
            ex.GetType().ToString())
    End Try
End Sub

.NET Framework
Available since 1.1
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