DataRelation.ChildKeyConstraint 属性

定义

命名空间:

System.Data

程序集:

System.Data.Common.dll

Source:

DataRelation.cs

获取关系的 ForeignKeyConstraint。

public:
 virtual property System::Data::ForeignKeyConstraint ^ ChildKeyConstraint { System::Data::ForeignKeyConstraint ^ get(); };

public virtual System.Data.ForeignKeyConstraint? ChildKeyConstraint { get; }

member this.ChildKeyConstraint : System.Data.ForeignKeyConstraint

Public Overridable ReadOnly Property ChildKeyConstraint As ForeignKeyConstraint

属性值

ForeignKeyConstraint

一个 ForeignKeyConstraint。

示例

以下示例为UpdateRule与 DataRelation关联的 设置 、 DeleteRule和 AcceptReject 规则ForeignKeyConstraint。

Private Sub SetChildKeyConstraint(dataSet As DataSet)
   ' Set child and parent columns.
   Dim parentColumn As DataColumn = dataSet.Tables( _
       "Suppliers").Columns("SupplierID")
   Dim childColumn As DataColumn = dataSet.Tables( _
       "Products").Columns("SupplierID")
   Dim relation As New DataRelation( _
       "SuppliersConstraint", parentColumn, childColumn)
   dataSet.Relations.Add(relation)

   Dim foreignKey As ForeignKeyConstraint = _
       relation.ChildKeyConstraint
   foreignKey.DeleteRule = Rule.SetNull
   foreignKey.UpdateRule = Rule.Cascade
   foreignKey.AcceptRejectRule = AcceptRejectRule.Cascade
End Sub

注解

如果此关系不存在关联 ForeignKeyConstraint ，则当将关系添加到关系集合时，将自动创建该关系，并由 ChildKeyConstraint指向该关系。

另请参阅

• AcceptRejectRule
• ParentKeyConstraint
• Rule