本文整理匯總了VB.NET中System.Data.Rule枚舉的典型用法代碼示例。如果您正苦於以下問題:VB.NET Rule枚舉的具體用法?VB.NET Rule怎麽用?VB.NET Rule使用的例子?那麽, 這裏精選的枚舉代碼示例或許可以為您提供幫助。
在下文中一共展示了Rule枚舉的1個代碼示例,這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚,您的評價將有助於係統推薦出更棒的VB.NET代碼示例。
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 fkeyConstraint As ForeignKeyConstraint
' Set parent and child column variables.
parentColumn = suppliersProducts.Tables("Suppliers").Columns("SupplierID")
childColumn = suppliersProducts.Tables("Products").Columns("SupplierID")
fkeyConstraint = New ForeignKeyConstraint( _
"SupplierFKConstraint", parentColumn, childColumn)
' Set null values when a value is deleted.
fkeyConstraint.DeleteRule = Rule.SetNull
fkeyConstraint.UpdateRule = Rule.Cascade
fkeyConstraint.AcceptRejectRule = AcceptRejectRule.Cascade
' Add the constraint, and set EnforceConstraints to true.
suppliersProducts.Tables("Products").Constraints.Add(fkeyConstraint)
suppliersProducts.EnforceConstraints = True
End Sub