AbsolutePosition 和 CursorLocation 屬性範例 (VB)

此範例示範 AbsolutePosition 屬性如何追蹤迴圈的進度，該迴圈列舉 Recordset 的所有記錄。 這會使用 CursorLocation 屬性，藉由將游標設定為用戶端資料指標來啟用 AbsolutePosition 屬性。

'BeginAbsolutePositionVB  
  
    'To integrate this code  
    'replace the data source and initial catalog values  
    'in the connection string  
  
Public Sub Main()  
    On Error GoTo ErrorHandler  
  
    'recordset and connection variables  
    Dim rstEmployees As ADODB.Recordset  
    Dim Cnxn As ADODB.Connection  
    Dim strCnxn As String  
    Dim strSQL As String  
        'record variables  
    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 Employee recordset with  
    ' Client-side cursor to enable AbsolutePosition property  
    Set rstEmployees = New ADODB.Recordset  
    strSQL = "employee"  
    rstEmployees.Open strSQL, strCnxn, adUseClient, adLockReadOnly, adCmdTable  
  
    ' Enumerate Recordset  
    Do While Not rstEmployees.EOF  
        ' Display current record information  
        strMessage = "Employee: " & rstEmployees!lname & vbCr & _  
            "(record " & rstEmployees.AbsolutePosition & _  
            " of " & rstEmployees.RecordCount & ")"  
        If MsgBox(strMessage, vbOKCancel) = vbCancel Then Exit Do  
        rstEmployees.MoveNext  
    Loop  
  
    ' 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  
'EndAbsolutePositionVB  

另請參閱

AbsolutePosition 屬性 (ADO)
CursorLocation 屬性 (ADO)
Recordset 物件 (ADO)