本文整理汇总了VB.NET中System.Data.DataSet.EnforceConstraints属性的典型用法代码示例。如果您正苦于以下问题:VB.NET DataSet.EnforceConstraints属性的具体用法?VB.NET DataSet.EnforceConstraints怎么用?VB.NET DataSet.EnforceConstraints使用的例子?那么恭喜您, 这里精选的属性代码示例或许可以为您提供帮助。您也可以进一步了解该属性所在类System.Data.DataSet
的用法示例。
在下文中一共展示了DataSet.EnforceConstraints属性的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的VB.NET代码示例。
示例1: DemonstrateEnforceConstraints
Private Sub DemonstrateEnforceConstraints()
' Create a DataSet with one table, one column and
' a UniqueConstraint.
Dim dataSet As New DataSet("dataSet")
Dim table As New DataTable("table")
Dim column As 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