Find-Methode – Beispiel (VB)
In diesem Beispiel wird die Find-Methode des Recordset-Objekts verwendet, um die Anzahl der Geschäftstitel in der Pubs-Datenbank zu finden und zu zählen. Im Beispiel wird davon ausgegangen, dass der zugrunde liegende Anbieter keine ähnliche Funktionalität unterstützt.
'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