DataRelation Constructor (String, DataColumn, DataColumn)

 

Initializes a new instance of the DataRelation class using the specified DataRelation name, and parent and child DataColumn objects.

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

Public Sub New (
	relationName As String,
	parentColumn As DataColumn,
	childColumn As DataColumn
)

Parameters

relationName
Type: System.String

The name of the DataRelation. If null or an empty string (""), a default name will be given when the created object is added to the DataRelationCollection.

parentColumn
Type: System.Data.DataColumn

The parent DataColumn in the relationship.

childColumn
Type: System.Data.DataColumn

The child DataColumn in the relationship.

Exception Condition
ArgumentNullException

One or both of the DataColumn objects contains null.

InvalidConstraintException

The columns have different data types

-Or-

The tables do not belong to the same DataSet.

The following example creates a new DataRelation and adds it to the DataRelationCollection of a DataSet.


 Private Sub CreateRelation()
    ' Code to get the DataSet not shown here.
    ' Get the DataColumn objects from two DataTable 
    ' objects in a DataSet.
    Dim parentCols() As DataColumn = New DataColumn() _
        {DataSet1.Tables("Customers").Columns("CustID"), _
        DataSet1.Tables("Customers").Columns("OrdID")}
    Dim childCols() As DataColumn = New DataColumn() _
        {DataSet1.Tables("Orders").Columns("CustID"), _
        DataSet1.Tables("Orders").Columns("OrdID")}

    ' Create DataRelation.
    Dim CustOrderRel As DataRelation = New DataRelation( _
        "CustomersOrders", parentCols, childCols)

    ' Add the relation to the DataSet.
    DataSet1.Relations.Add(CustOrderRel)
End Sub

.NET Framework
Available since 1.1
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