DataRelationCollection.Add Method (String, DataColumn[], DataColumn[])


The .NET API Reference documentation has a new home. Visit the .NET API Browser on to see the new experience.

Creates a DataRelation with the specified name and arrays of parent and child columns, and adds it to the collection.

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

public virtual DataRelation Add(
	string name,
	DataColumn[] parentColumns,
	DataColumn[] childColumns


Type: System.String

The name of the DataRelation to create.

Type: System.Data.DataColumn[]

An array of parent DataColumn objects.

Type: System.Data.DataColumn[]

An array of child DataColumn objects.

Return Value

Type: System.Data.DataRelation

The created DataRelation.

Exception Condition

The relation name is a null value.


The relation already belongs to this collection, or it belongs to another collection.


The collection already has a relation with the same name. (The comparison is not case sensitive.)


The relation has entered an invalid state since it was created.

If the relation is successfully added to the collection, the CollectionChanged event occurs.

When a DataRelation object is added to the collection, ForeignKeyConstraint and UniqueConstraint objects are created by default if they do not already exist.

private void AddRelation() 
    DataTable table = new DataTable();
    DataColumn column1 = table.Columns.Add("Column1");
    DataColumn column2 = table.Columns.Add("Column2");
    table.ChildRelations.Add("New Relation", column1, column2);

.NET Framework
Available since 1.1
Return to top