Gets a value indicating whether or not the constraint is on a primary key.
Assembly: System.Data (in System.Data.dll)
A table usually includes a primary key that ensures every row is unique. In some tables, the primary key may be made up of more than one column. For example, a primary key for a table containing names might be made up of both the first and last names as well. To create a primary key with more than one column, set the Columns property to an array of DataColumn objects.
The following example checks the property.
Private Sub GetPrimaryKey() Dim dataRelation As DataRelation Dim uniqueConstraint As UniqueConstraint ' Get a DataRelation from a DataSet. dataRelation = DataSet1.Relations("CustomerOrders") ' Get the ParentKeyConstraint. uniqueConstraint = dataRelation.ParentKeyConstraint ' Test if the IsPrimaryKey is true. If uniqueConstraint.IsPrimaryKey Then Console.WriteLine("IsPrimaryKey=True") Else Console.WriteLine("IsPrimaryKey=False") End If End Sub
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.