DataRelation Constructor (String, DataColumn, DataColumn, Boolean)

DataRelation Constructor (String, DataColumn, DataColumn, Boolean)

 

Initializes a new instance of the DataRelation class using the specified name, parent and child DataColumn objects, and a value that indicates whether to create constraints.

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

public DataRelation(
	string relationName,
	DataColumn parentColumn,
	DataColumn childColumn,
	bool createConstraints
)

Parameters

relationName
Type: System.String

The name of the relation. 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 relation.

childColumn
Type: System.Data.DataColumn

The child DataColumn in the relation.

createConstraints
Type: System.Boolean

A value that indicates whether constraints are created. true, if constraints are created. Otherwise, false.

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 parentColumn As DataColumn = DataSet1.Tables( _
        "Customers").Columns("CustID")
    Dim childColumn As DataColumn = _
        DataSet1.Tables("Orders").Columns("CustID")

    ' Create DataRelation.
    Dim bConstraints As Boolean = True
    Dim customerOrdersRelation As DataRelation = _
        New DataRelation("CustomersOrders", _
        parentColumn, childColumn, bConstraints)

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

.NET Framework
Available since 1.1
Return to top
Show:
© 2016 Microsoft