NGWS SDK Documentation  

This is preliminary documentation and subject to change.
To comment on this topic, please send us email at ngwssdk@microsoft.com. Thanks!

DataRelation Constructor (String, DataColumn, DataColumn, Boolean)

Initializes a new instance of the DataRelation class using the specified name, parent, and child columns, and value to create constraints.

[Visual Basic]
Overloads Public Sub New( _
   ByVal relationName As String, _
   ByVal parentColumn As DataColumn, _
   ByVal childColumn As DataColumn, _
   ByVal createConstraints As Boolean _
)
[C#]
public DataRelation(
   string relationName,
   DataColumn parentColumn,
   DataColumn childColumn,
   bool createConstraints
);
[C++]
public: DataRelation(
   String* relationName,
   DataColumn* parentColumn,
   DataColumn* childColumn,
   bool createConstraints
);
[JScript]
public function DataRelation(
   relationName : String,
   parentColumn : DataColumn,
   childColumn : DataColumn,
   createConstraints : Boolean
);

Parameters

relationName
The name of the relation. If a null reference (in Visual Basic Nothing) or an empty string (""), a default name will be given when the created object is added to the RelationsCollection.
parentColumn
The parent DataColumn in the relation.
childColumn
The child DataColumn in the relation.
createConstraints
[To be supplied.]

Exceptions

Exception Type Condition
ArgumentNullException Either one or both of the DataColumns is a a null reference (Nothing).
InvalidConstraintException The columns have differing data types

-Or-

The tables don't belong to the same DataSet.

Example [Visual Basic]

The following example creates a new DataRelation and adds it to a DataSet object's RelationsCollection.

[Visual Basic]

Private Sub CreateRelation()
   ' Get the DataColumn objects from two DataTable objects in a DataSet.
   Dim parentCol As DataColumn
   Dim childCol As DataColumn
   ' Code to get the DataSet not shown here.
   parentCol = DataSet1.Tables("Customers").Columns("CustID")
   childCol = DataSet1.Tables("Orders").Columns("CustID")
   Dim bConstraints As Boolean
   bConstraints = True
   ' Create DataRelation.
   Dim relCustOrder As DataRelation
   CustOrderRel = New DataRelation("CustomersOrders", parentCol, childCol, bConstraints)
   ' Add the relation to the DataSet.
   DataSet1.Relations.Add(CustOrderRel)
End Sub

See Also

DataRelation Class | DataRelation Members | System.Data Namespace | DataRelation Constructor Overload List | DataColumn | ForeignKeyConstraint | RelationName