Source-Eigenschaft – Beispiel (VB)
In diesem Beispiel wird die Verwendung der Source-Eigenschaft veranschaulicht, indem drei Recordset-Objekte basierend auf verschiedenen Datenquellen geöffnet werden.
'BeginSourceVB
'To integrate this code
'replace the data source and initial catalog values
'in the connection string
Public Sub Main()
On Error GoTo ErrorHandler
Dim Cnxn As ADODB.Connection
Dim rstTitles As ADODB.Recordset
Dim rstPublishers As ADODB.Recordset
Dim rstPublishersDirect As ADODB.Recordset
Dim rstTitlesPublishers As ADODB.Recordset
Dim cmdSQL As ADODB.Command
Dim strCnxn As String
Dim strSQL As String
' Open a connection
Set Cnxn = New ADODB.Connection
strCnxn = "Provider='sqloledb';Data Source='MySqlServer';" & _
"Initial Catalog='Pubs';Integrated Security='SSPI';"
Cnxn.Open strCnxn
' Open a recordset based on a command object
Set cmdSQL = New ADODB.Command
Set cmdSQL.ActiveConnection = Cnxn
strSQL = "Select title, type, pubdate FROM Titles ORDER BY title"
cmdSQL.CommandText = strSQL
Set rstTitles = cmdSQL.Execute()
' Open a recordset based on a table
Set rstPublishers = New ADODB.Recordset
strSQL = "Publishers"
rstPublishers.Open strSQL, Cnxn, adOpenStatic, adLockReadOnly, adCmdTable
'rstPublishers.Open strSQL, Cnxn, , , adCmdTable
' the above two lines of code are identical
' Open a recordset based on a table
Set rstPublishersDirect = New ADODB.Recordset
rstPublishersDirect.Open strSQL, strCnxn, , , adCmdTableDirect
' Open a recordset based on a SQL string.
Set rstTitlesPublishers = New ADODB.Recordset
strSQL = "SELECT title_ID AS TitleID, title AS Title, " & _
"publishers.pub_id AS PubID, pub_name AS PubName " & _
"FROM publishers INNER JOIN Titles " & _
"ON publishers.pub_id = Titles.pub_id " & _
"ORDER BY Title"
rstTitlesPublishers.Open strSQL, strCnxn, , , adCmdText
' Use the Source property to display the source of each recordset.
MsgBox "rstTitles source: " & vbCr & _
rstTitles.Source & vbCr & vbCr & _
"rstPublishers source: " & vbCr & _
rstPublishers.Source & vbCr & vbCr & _
"rstPublishersDirect source: " & vbCr & _
rstPublishersDirect.Source & vbCr & vbCr & _
"rstTitlesPublishers source: " & vbCr & _
rstTitlesPublishers.Source
' clean up
rstTitles.Close
rstPublishers.Close
rstTitlesPublishers.Close
Cnxn.Close
Set rstTitles = Nothing
Set rstPublishers = Nothing
Set rstTitlesPublishers = 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 rstPublishers Is Nothing Then
If rstPublishers.State = adStateOpen Then rstPublishers.Close
End If
Set rstPublishers = Nothing
If Not rstTitlesPublishers Is Nothing Then
If rstTitlesPublishers.State = adStateOpen Then rstTitlesPublishers.Close
End If
Set rstTitlesPublishers = 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
'EndSourceVB