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UniqueConstraint.Columns Property

Definition

Gets the array of columns that this constraint affects.

public:
 virtual property cli::array <System::Data::DataColumn ^> ^ Columns { cli::array <System::Data::DataColumn ^> ^ get(); };
public virtual System.Data.DataColumn[] Columns { get; }
[System.Data.DataSysDescription("KeyConstraintColumnsDescr")]
public virtual System.Data.DataColumn[] Columns { get; }
member this.Columns : System.Data.DataColumn[]
[<System.Data.DataSysDescription("KeyConstraintColumnsDescr")>]
member this.Columns : System.Data.DataColumn[]
Public Overridable ReadOnly Property Columns As DataColumn()

Property Value

An array of DataColumn objects.

Attributes

Examples

The following example returns the DataColumn objects that the UniqueConstraint constrains.

Private Sub GetColsFromConstraint()
    Dim dataColumns() As DataColumn

    ' Get a named relation from a DataSet.
    Dim dataRelation As DataRelation
    dataRelation = DataSet1.Relations("CustomerOrders")

    ' Get the ParentKeyConstraint
    Dim uniqueConstraint As UniqueConstraint
    uniqueConstraint= dataRelation.ParentKeyConstraint

    ' Get the DataColumn objects being constrained.
    dataColumns = uniqueConstraint.Columns

    ' Print the column name of each column.
    Dim i As Integer
    For i = 0 to dataColumns.GetUpperBound(0)
       Console.Write(dataColumns(i).ColumnName)
    Next i
 End Sub

Applies to

See also