Provider 和 DefaultDatabase 属性示例 (VB)

此示例通过使用不同的提供程序打开三个 Connection 对象来演示 Provider 属性。 它还使用 DefaultDatabase 属性为 Microsoft ODBC 提供程序设置默认数据库。

注意

如果要连接到支持 Windows 身份验证的数据源提供程序，则应指定 Trusted_Connection=yes 或 Integrated Security = SSPI，而不是连接字符串中的用户 ID 和密码信息。

'BeginProviderVB  
  
    'To integrate this code  
    'replace the data source and initial catalog values  
    'in the connection strings  
  
Public Sub Main()  
    On Error GoTo ErrorHandler  
  
    Dim Cnxn1 As ADODB.Connection  
    Dim Cnxn2 As ADODB.Connection  
    Dim Cnxn3 As ADODB.Connection  
    Dim strCnxn As String  
  
    ' Open a connection using the Microsoft ODBC provider  
    Set Cnxn1 = New ADODB.Connection  
    Cnxn1.ConnectionString = "driver={SQL Server};server='MySqlServer';" & _  
        "user id='MyUserID';password='MyPassword';"  
    Cnxn1.Open strCnxn  
    Cnxn1.DefaultDatabase = "Pubs"  
  
    ' Display the provider  
    MsgBox "Cnxn1 provider: " & Cnxn1.Provider  
  
    ' Open a connection using the Microsoft Jet provider  
    Set Cnxn2 = New ADODB.Connection  
    Cnxn2.Provider = "Microsoft.Jet.OLEDB.4.0"  
    Cnxn2.Open "Northwind.mdb", _  
        "MyUserID", "MyPassword"  
  
    ' Display the provider.  
    MsgBox "Cnxn2 provider: " & Cnxn2.Provider  
  
    ' Open a connection using the Microsoft SQL Server provider  
    Set Cnxn3 = New ADODB.Connection  
    Cnxn3.Provider = "sqloledb"  
    Cnxn3.Open "Data Source='MySqlServer';" & _  
        "Initial Catalog='Pubs';Integrated Security='SSPI';"  
  
    ' Display the provider  
    MsgBox "Cnxn3 provider: " & Cnxn3.Provider  
  
    ' clean up  
    Cnxn1.Close  
    Cnxn2.Close  
    Cnxn3.Close  
    Set Cnxn1 = Nothing  
    Set Cnxn2 = Nothing  
    Set Cnxn3 = Nothing  
    Exit Sub  
  
ErrorHandler:  
    If Not Cnxn1 Is Nothing Then  
        If Cnxn1.State = adStateOpen Then Cnxn1.Close  
    End If  
    Set Cnxn1 = Nothing  
  
    If Not Cnxn2 Is Nothing Then  
        If Cnxn2.State = adStateOpen Then Cnxn2.Close  
    End If  
    Set Cnxn2 = Nothing  
  
    If Not Cnxn3 Is Nothing Then  
        If Cnxn3.State = adStateOpen Then Cnxn3.Close  
    End If  
    Set Cnxn3 = Nothing  
  
    If Err <> 0 Then  
        MsgBox Err.Source & "-->" & Err.Description, , "Error"  
    End If  
  
End Sub  
'EndProviderVB  

另请参阅

连接对象 (ADO)
DefaultDatabase 属性
Provider 属性 (ADO)