本文整理汇总了VB.NET中System.Data.ForeignKeyConstraint.UpdateRule属性的典型用法代码示例。如果您正苦于以下问题:VB.NET ForeignKeyConstraint.UpdateRule属性的具体用法?VB.NET ForeignKeyConstraint.UpdateRule怎么用?VB.NET ForeignKeyConstraint.UpdateRule使用的例子?那么, 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.ForeignKeyConstraint
的用法示例。
在下文中一共展示了ForeignKeyConstraint.UpdateRule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: CreateConstraint
' The next line goes into the Declarations section of the module:
' SuppliersProducts is a class derived from DataSet.
Private suppliersProducts As SuppliersProducts
Private Sub CreateConstraint()
' Declare parent column and child column variables.
Dim parentColumn As DataColumn
Dim childColumn As DataColumn
Dim fkConstraint As ForeignKeyConstraint
' Set parent and child column variables.
parentColumn = suppliersProducts.Tables("Suppliers").Columns("SupplierID")
childColumn = suppliersProducts.Tables("Products").Columns("SupplieriD")
fkConstraint = New ForeignKeyConstraint( _
"SuppierFKConstraint", parentColumn, childColumn)
' Set null values when a value is deleted.
fkConstraint.DeleteRule = Rule.SetNull
fkConstraint.UpdateRule = Rule.Cascade
fkConstraint.AcceptRejectRule = AcceptRejectRule.Cascade
' Add the constraint, and set EnforceConstraints to true.
suppliersProducts.Tables("Suppliers").Constraints.Add(fkConstraint)
suppliersProducts.EnforceConstraints = True
End Sub