Update- und CancelUpdate-Methode – Beispiel (VB)

In diesem Beispiel wird die Verwendung der Update-Methode in Verbindung mit der CancelUpdate-Methode veranschaulicht.

'BeginUpdateVB  
Public Sub Main()  
    On Error GoTo ErrorHandler  
  
    'To integrate this code  
    'replace the data source and initial catalog values  
    'in the connection string  
  
    ' recordset and connection variables  
    Dim rstEmployees As ADODB.Recordset  
    Dim Cnxn As ADODB.Connection  
    Dim strCnxn As String  
    Dim strSQLEmployees As String  
     ' buffer variables  
    Dim strOldFirst As String  
    Dim strOldLast As String  
    Dim strMessage As String  
  
    ' Open connection  
    Set Cnxn = New ADODB.Connection  
    strCnxn = "Provider='sqloledb';Data Source='MySqlServer';" & _  
        "Initial Catalog='Pubs';Integrated Security='SSPI';"  
    Cnxn.Open strCnxn  
  
    ' Open recordset to enable changes  
    Set rstEmployees = New ADODB.Recordset  
    strSQLEmployees = "SELECT fname, lname FROM Employee ORDER BY lname"  
    rstEmployees.Open strSQLEmployees, Cnxn, adOpenKeyset, adLockOptimistic, adCmdText  
  
    ' Store original data  
    strOldFirst = rstEmployees!fname  
    strOldLast = rstEmployees!lname  
    ' Change data in edit buffer  
    rstEmployees!fname = "Linda"  
    rstEmployees!lname = "Kobara"  
  
    ' Show contents of buffer and get user input  
    strMessage = "Edit in progress:" & vbCr & _  
        "  Original data = " & strOldFirst & " " & _  
        strOldLast & vbCr & "  Data in buffer = " & _  
        rstEmployees!fname & " " & rstEmployees!lname & vbCr & vbCr & _  
        "Use Update to replace the original data with " & _  
        "the buffered data in the Recordset?"  
  
    If MsgBox(strMessage, vbYesNo) = vbYes Then  
        rstEmployees.Update  
    Else  
        rstEmployees.CancelUpdate  
    End If  
  
    ' show the resulting data  
    MsgBox "Data in recordset = " & rstEmployees!fname & " " & _  
       rstEmployees!lname  
  
    ' restore original data because this is a demonstration  
    If Not (strOldFirst = rstEmployees!fname And _  
           strOldLast = rstEmployees!lname) Then  
        rstEmployees!fname = strOldFirst  
        rstEmployees!lname = strOldLast  
        rstEmployees.Update  
    End If  
  
    ' clean up  
    rstEmployees.Close  
    Cnxn.Close  
    Set rstEmployees = Nothing  
    Set Cnxn = Nothing  
    Exit Sub  
  
ErrorHandler:  
    ' clean up  
    If Not rstEmployees Is Nothing Then  
        If rstEmployees.State = adStateOpen Then rstEmployees.Close  
    End If  
    Set rstEmployees = Nothing  
  
    If Not Cnxn Is Nothing Then  
        If Cnxn.State = adStateOpen Then Cnxn.Close  
    End If  
    Set Cnxn = Nothing  
  
    If Err <> 0 Then  
        MsgBox Err.Source & "-->" & Err.Description, , "Error"  
    End If  
End Sub  
' EndUpdateVB  

In diesem Beispiel wird die Verwendung der Update-Methode in Verbindung mit der AddNew-Methode veranschaulicht.

Attribute VB_Name = "Update"  

Weitere Informationen

CancelUpdate-Methode (ADO)
Recordset-Objekt (ADO)
Update-Methode