DataSet.EnforceConstraints Property
Assembly: System.Data (in system.data.dll)
'Declaration Public Property EnforceConstraints As Boolean 'Usage Dim instance As DataSet Dim value As Boolean value = instance.EnforceConstraints instance.EnforceConstraints = value
/** @property */ public boolean get_EnforceConstraints () /** @property */ public void set_EnforceConstraints (boolean value)
public function get EnforceConstraints () : boolean public function set EnforceConstraints (value : boolean)
Property Value
true if rules are enforced; otherwise false. The default is true.Constraints are set at the DataTable level (Constraints property). For more information about creating constraints, see Adding Constraints to a Table.
The following example creates a DataSet with one table, one column, five rows, and one UniqueConstraint. The EnforceConstraints property is set to false and the values of each row are set to the same value. When the EnforceConstraints property is reset to true, a ConstraintException is generated.
Private Sub DemonstrateEnforceConstraints() ' Create a DataSet with one table, one column and ' a UniqueConstraint. Dim dataSet As DataSet = New DataSet("dataSet") Dim table As DataTable = New DataTable("table") Dim column As DataColumn = New DataColumn("col1") column.Unique = True table.Columns.Add(column) dataSet.Tables.Add(table) Console.WriteLine("constraints.count: " _ & table.Constraints.Count) ' add five rows. Dim row As DataRow Dim i As Integer For i = 0 To 4 row = table.NewRow() row("col1") = i table.Rows.Add(row) Next table.AcceptChanges() dataSet.EnforceConstraints = False ' Change the values of all rows to 1. Dim thisRow As DataRow For Each thisRow In table.rows thisRow("col1") = 1 Next Try dataSet.EnforceConstraints = True Catch e As System.Data.ConstraintException ' Process exception and return. Console.WriteLine("Exception of type {0 occurred.", _ e.GetType().ToString()) End Try End Sub
Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.