Supports Method Example (VB)

Microsoft ActiveX Data Objects (ADO)

ADO 2.5 Samples

Supports Method Example (VB)

This example uses the Supports method to display the options supported by a recordset opened with different cursor types. The DisplaySupport procedure is required for this procedure to run.

'BeginSupportsVB

    '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 rstTitles As ADODB.Recordset
    Dim Cnxn As ADODB.Connection
    Dim strCnxn As String
    Dim strSQLTitles As String
     ' array variables
    Dim arrCursorType(4) As Integer
    Dim intIndex As Integer
    
    ' open connection
    Set Cnxn = New ADODB.Connection
    strCnxn = "Provider='sqloledb';Data Source='MySqlServer';" & _
        "Initial Catalog='Pubs';Integrated Security='SSPI';"
    Cnxn.Open strCnxn
    
    ' Fill array with CursorType constants
    arrCursorType(0) = adOpenForwardOnly
    arrCursorType(1) = adOpenKeyset
    arrCursorType(2) = adOpenDynamic
    arrCursorType(3) = adOpenStatic
    
    ' open recordset using each CursorType and optimistic locking
    For intIndex = 0 To 3
        Set rstTitles = New ADODB.Recordset
        rstTitles.CursorType = arrCursorType(intIndex)
        rstTitles.LockType = adLockOptimistic
        
        strSQLTitles = "Titles"
        rstTitles.Open strSQLTitles, Cnxn, , , adCmdTable
        
        Select Case arrCursorType(intIndex)
           Case adOpenForwardOnly
              Debug.Print "ForwardOnly cursor supports:"
           Case adOpenKeyset
              Debug.Print "Keyset cursor supports:"
           Case adOpenDynamic
              Debug.Print "Dynamic cursor supports:"
           Case adOpenStatic
              Debug.Print "Static cursor supports:"
        End Select
        
        ' call the DisplaySupport procedure from below
        ' to display the supported options
        DisplaySupport rstTitles
       
    Next intIndex
   
    ' 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
'EndSupportsVB



'BeginSupports2VB
Public Sub DisplaySupport(rstTemp As ADODB.Recordset)

   Dim arrConstants(11) As Long
   Dim blnSupports As Boolean
   Dim intIndex As Integer

   ' Fill array with cursor option constants
   arrConstants(0) = adAddNew
   arrConstants(1) = adApproxPosition
   arrConstants(2) = adBookmark
   arrConstants(3) = adDelete
   arrConstants(4) = adFind
   arrConstants(5) = adHoldRecords
   arrConstants(6) = adMovePrevious
   arrConstants(7) = adNotify
   arrConstants(8) = adResync
   arrConstants(9) = adUpdate
   arrConstants(10) = adUpdateBatch
   
   For intIndex = 0 To 10
      blnSupports = _
         rstTemp.Supports(arrConstants(intIndex))
      If blnSupports Then
         Select Case arrConstants(intIndex)
            Case adAddNew
               Debug.Print "   AddNew"
            Case adApproxPosition
               Debug.Print "   AbsolutePosition and AbsolutePage"
            Case adBookmark
               Debug.Print "   blnkmark"
            Case adDelete
               Debug.Print "   Delete"
            Case adFind
               Debug.Print "   Find"
            Case adHoldRecords
               Debug.Print "   Holding Records"
            Case adMovePrevious
               Debug.Print "   MovePrevious and Move"
            Case adNotify
               Debug.Print "   Notifications"
            Case adResync
               Debug.Print "   Resyncing data"
            Case adUpdate
               Debug.Print "   Update"
            Case adUpdateBatch
               Debug.Print "   batch updating"
         End Select
      End If
   Next intIndex

End Sub
'EndSupports2VB

See Also

Recordset Object | Supports Method

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