项 Append 方法、项 Type、RelatedColumn、RelatedTable 和 UpdateRule 属性示例 (VB)

以下代码演示了如何在名为 Customers 和 Orders 的两个现有表之间创建新的外键关系。

' BeginCreateKeyVB  
Sub Main()  
    On Error GoTo CreateKeyError  
  
    Dim kyForeign As New ADOX.Key  
    Dim cat As New ADOX.Catalog  
  
    ' Connect to the catalog.  
    cat.ActiveConnection = "Provider='Microsoft.Jet.OLEDB.4.0';" & _  
        "Data Source='Northwind.mdb';"  
  
    ' Define the foreign key.  
    kyForeign.Name = "CustOrder"  
    kyForeign.Type = adKeyForeign  
    kyForeign.RelatedTable = "Customers"  
    kyForeign.Columns.Append "CustomerId"  
    kyForeign.Columns("CustomerId").RelatedColumn = "CustomerId"  
    kyForeign.UpdateRule = adRICascade  
  
    ' Append the foreign key to the keys collection.  
    cat.Tables("Orders").Keys.Append kyForeign  
  
    'Delete the key t demonstrate the Delete method.  
    cat.Tables("Orders").Keys.Delete kyForeign.Name  
  
    'Clean up.  
    Set cat.ActiveConnection = Nothing  
    Set cat = Nothing  
    Set kyForeign = Nothing  
    Exit Sub  
  
CreateKeyError:  
    Set cat = Nothing  
    Set kyForeign = Nothing  
  
    If Err <> 0 Then  
        MsgBox Err.Source & "-->" & Err.Description, , "Error"  
    End If  
  
End Sub  
' EndCreateKeyVB  

另请参阅

Append 方法（ADOX 列）
Append 方法（ADOX 项）
目录对象 (ADOX)
列对象 (ADOX)
列集合 (ADOX)
项对象 (ADOX)
项集合 (ADOX)
Name 属性 (ADOX)
RelatedColumn 属性 (ADOX)
RelatedTable 属性 (ADOX)
表对象 (ADOX)
表集合 (ADOX)
Type 属性（项）(ADOX)
UpdateRule 属性 (ADOX)