ConnectionString、ConnectionTimeout、および状態のプロパティの例 (VB)ConnectionString, ConnectionTimeout, and State Properties Example (VB)

この例を使用してさまざまな方法を示しています、 ConnectionStringプロパティを開き、接続オブジェクト。This example demonstrates different ways of using the ConnectionString property to open a Connection object. またを使用して、 ConnectionTimeout接続タイムアウトを設定するプロパティと状態接続の状態を確認するプロパティ。It also uses the ConnectionTimeout property to set a connection timeout period, and the State property to check the state of the connections. GetState 関数は、この手順を実行する必要があります。The GetState function is required for this procedure to run.


Windows 認証をサポートするデータ ソース プロバイダーに接続するかどうかは、する必要がありますを指定するTrusted_Connection = yesまたはIntegrated Security = SSPIユーザー ID とパスワードの代わりに接続文字列の情報です。If you are connecting to a data source provider that supports Windows authentication, you should specify Trusted_Connection=yes or Integrated Security = SSPI instead of user ID and password information in the connection string.

    'To integrate this code replace  
    'the database, DSN or Data Source values  
Public Sub Main()  
    On Error GoTo ErrorHandler  
    Dim Cnxn1 As ADODB.Connection  
    Dim Cnxn2 As ADODB.Connection  
    Dim Cnxn3 As ADODB.Connection  
    Dim Cnxn4 As ADODB.Connection  
     ' Open a connection without using a Data Source Name (DSN)  
    Set Cnxn1 = New ADODB.Connection  
    Cnxn1.ConnectionString = "Provider='sqloledb';Data Source='MySqlServer';" & _  
        "Initial Catalog='Pubs';Integrated Security='SSPI';"  
    MsgBox "Cnxn1 state: " & GetState(Cnxn1.State)  
     ' Open a connection using a DSN and ODBC tags  
     ' It is assumed that you have created DSN 'Pubs' with a user name as  
     ' 'MyUserId' and password as 'MyPassword'.  
    Set Cnxn2 = New ADODB.Connection  
    Cnxn2.ConnectionString = "Data Source='Pubs';" & _  
        "User ID='MyUserId';Password='MyPassword';"  
    Cnxn2.ConnectionTimeout = 30  
    MsgBox "Cnxn2 state: " & GetState(Cnxn2.State)  
     ' Open a connection using a DSN and OLE DB tags  
     ' It is assumed that you have created DSN 'Pubs1' with windows authentication.  
    Set Cnxn3 = New ADODB.Connection  
    Cnxn3.ConnectionString = "Data Source='Pubs1';"  
    MsgBox "Cnxn2 state: " & GetState(Cnxn3.State)  
     ' Open a connection using a DSN and individual  
     ' arguments instead of a connection string  
     ' It is assumed that you have created DSN 'Pubs' with a user name as  
     ' 'MyUserId' and password as 'MyPassword'.  
    Set Cnxn4 = New ADODB.Connection  
    Cnxn4.Open "Pubs", "MyUserId", "MyPassword"  
    MsgBox "Cnxn4 state: " & GetState(Cnxn4.State)  
    ' clean up  
    Set Cnxn1 = Nothing  
    Set Cnxn2 = Nothing  
    Set Cnxn3 = Nothing  
    Set Cnxn4 = Nothing  
    Exit Sub  
    ' clean up  
    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 Not Cnxn4 Is Nothing Then  
        If Cnxn4.State = adStateOpen Then Cnxn4.Close  
    End If  
    Set Cnxn4 = Nothing  
    If Err <> 0 Then  
        MsgBox Err.Source & "-->" & Err.Description, , "Error"  
    End If  
End Sub  
Public Function GetState(intState As Integer) As String  
   Select Case intState  
      Case adStateClosed  
         GetState = "adStateClosed"  
      Case adStateOpen  
         GetState = "adStateOpen"  
   End Select  
End Function  

関連項目See Also

接続オブジェクト (ADO) Connection Object (ADO)
ConnectionString プロパティ (ADO) ConnectionString Property (ADO)
ConnectionTimeout プロパティ (ADO) ConnectionTimeout Property (ADO)
State プロパティ (ADO)State Property (ADO)