ForeignKeyConstraint.AcceptRejectRule 属性

定义

命名空间:

System.Data

程序集:

System.Data.Common.dll

Source:

ForeignKeyConstraint.cs

指示调用 AcceptChanges() 时，通过该约束应发生的操作。

public:
 virtual property System::Data::AcceptRejectRule AcceptRejectRule { System::Data::AcceptRejectRule get(); void set(System::Data::AcceptRejectRule value); };

public virtual System.Data.AcceptRejectRule AcceptRejectRule { get; set; }

member this.AcceptRejectRule : System.Data.AcceptRejectRule with get, set

Public Overridable Property AcceptRejectRule As AcceptRejectRule

属性值

AcceptRejectRule

AcceptRejectRule 值之一。 可能的值包括 None 和 Cascade。 默认值为 None。

示例

以下示例创建 一个 ForeignKeyConstraint，设置其 AcceptRejectRule，并将约束添加到 DataTable 对象的 ConstraintCollection。

' 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

注解

在调用 方法之前，AcceptChanges对 DataRow 或 DataTable 的更改不是最终的。 此时， AcceptRejectRule 确定对已更改或删除的任何值的操作过程。

另请参阅

• AcceptRejectRule