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Clone method example (VB)

Applies to: Access 2013, Office 2013

This example uses the Clone method to create copies of a Recordset and then lets the user position the record pointer of each copy independently.

 
'BeginCloneVB 
 
 'To integrate this code 
 'replace the data source and initial catalog values 
 'in the connection string 
 
Public Sub Main() 
 On Error GoTo ErrorHandler 
 
 'recordset array and connection variables 
 Dim arstStores(1 To 3) As ADODB.Recordset 
 Dim Cnxn As ADODB.Connection 
 Dim strSQLStore As String 
 Dim strCnxn As String 
 'record variables 
 Dim intLoop As Integer 
 Dim strMessage As String 
 Dim strFind 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 recordset as a static cursor type recordset 
 Set arstStores(1) = New ADODB.Recordset 
 strSQLStore = "SELECT stor_name FROM Stores ORDER BY stor_name" 
 arstStores(1).Open strSQLStore, strCnxn, adOpenStatic, adLockBatchOptimistic, adCmdText 
 
 ' Create two clones of the original Recordset 
 Set arstStores(2) = arstStores(1).Clone 
 Set arstStores(3) = arstStores(1).Clone 
 
 ' Loop through the array so that on each pass the user 
 ' is searching a different copy of the same Recordset 
 Do 
 For intLoop = 1 To 3 
 ' Ask for search string while showing where 
 ' the current record pointer is for each Recordset 
 strMessage = _ 
 "Recordsets from stores table:" & vbCr & _ 
 " 1 - Original - Record pointer at " & arstStores(1)!stor_name & vbCr & _ 
 " 2 - Clone - Record pointer at " & arstStores(2)!stor_name & vbCr & _ 
 " 3 - Clone - Record pointer at " & arstStores(3)!stor_name & vbCr & _ 
 "Enter search string for #" & intLoop & ":" 
 
 strFind = Trim(InputBox(strMessage)) 
 ' make sure something was entered, if not then EXIT loop 
 If strFind = "" Then Exit Do 
 
 ' otherwise locate the record from the entered string 
 arstStores(intLoop).Filter = "stor_name = '" & strFind & "'" 
 
 'if there's no match, jump to the last record 
 If arstStores(intLoop).EOF Then 
 arstStores(intLoop).Filter = adFilterNone 
 arstStores(intLoop).MoveLast 
 Else 
 MsgBox "Found " & strFind 
 End If 
 Next intLoop 
 Loop 
 
 ' clean up 
 arstStores(1).Close 
 arstStores(2).Close 
 arstStores(3).Close 
 Cnxn.Close 
 Set arstStores(1) = Nothing 
 Set arstStores(2) = Nothing 
 Set arstStores(3) = Nothing 
 Set Cnxn = Nothing 
 Exit Sub 
 
ErrorHandler: 
 ' clean up 
 If Not arstStores(1) Is Nothing Then 
 If arstStores(1).State = adStateOpen Then arstStores(1).Close 
 End If 
 Set arstStores(1) = Nothing 
 If Not arstStores(2) Is Nothing Then 
 If arstStores(2).State = adStateOpen Then arstStores(2).Close 
 End If 
 Set arstStores(2) = Nothing 
 If Not arstStores(3) Is Nothing Then 
 If arstStores(3).State = adStateOpen Then arstStores(3).Close 
 End If 
 Set arstStores(3) = 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 
'EndCloneVB