Esempio del metodo Find (VB)

In questo esempio si usa il metodo Find dell'oggetto Recordset per individuare e conteggiare il numero di titoli aziendali nel database Pubs. L'esempio presuppone che il provider sottostante non supporti funzionalità simili.

'BeginFindVB  
  
    'To integrate this code  
    'replace the data source and initial catalog values  
    'in the connection string  
  
Public Sub Main()  
    On Error GoTo ErrorHandler  
  
     ' connection and recordset variables  
    Dim Cnxn As New ADODB.Connection  
    Dim rstTitles As New ADODB.Recordset  
    Dim strCnxn As String  
    Dim strSQLTitles As String  
  
     ' record variables  
    Dim mark As Variant  
    Dim count As Integer  
  
     ' open connection  
    Set Cnxn = New ADODB.Connection  
    strCnxn = "Provider='sqloledb';Data Source='MySqlServer';" & _  
        "Initial Catalog='Pubs';Integrated Security='SSPI';"  
    Cnxn.Open strCnxn  
  
    ' open recordset with default parameters which are  
    ' sufficient to search forward through a Recordset  
    Set rstTitles = New ADODB.Recordset  
    strSQLTitles = "SELECT title_id FROM titles"  
    rstTitles.Open strSQLTitles, Cnxn, adOpenStatic, adLockReadOnly, adCmdText  
  
    count = 0  
    rstTitles.Find "title_id LIKE 'BU%'"  
  
    Do While Not rstTitles.EOF  
        'continue if last find succeeded  
        Debug.Print "Title ID: "; rstTitles!title_id  
        'count the last title found  
        count = count + 1  
        ' note current position  
        mark = rstTitles.Bookmark  
        rstTitles.Find "title_id LIKE 'BU%'", 1, adSearchForward, mark  
        ' above code skips current record to avoid finding the same row repeatedly;  
        ' last arg (bookmark) is redundant because Find searches from current position  
    Loop  
  
    Debug.Print "The number of business titles is " & count  
  
    ' clean up  
    rstTitles.Close  
    Cnxn.Close  
    Set rstTitles = Nothing  
    Set Cnxn = Nothing  
    Exit Sub  
  
ErrorHandler:  
    ' clean up  
    If Not rstTitles Is Nothing Then  
        If rstTitles.State = adStateOpen Then rstTitles.Close  
    End If  
    Set rstTitles = 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  
'EndFindVB  

Vedere anche

Metodo Find (ADO)
Oggetto Recordset (ADO)