How to Use ADO with Visual Basic

MORE INFORMATION

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FileName	Size	Date
AdoDemo.mdb	332KB	7/28/97
AdoVB	18KB	8/5/97
AdoVB.vbp	1KB	8/5/97
AdoVbEx	6KB	7/28/97

What Adovb Demonstrates

Adovb demonstrates proper use of output and return parameters (for SQL Server), and opening a parameterized recordset for both a Microsoft Access and SQL Server data sources. Also included is a generic template for error handling with ADO code:

   Private Sub cmdTemplate_Click()
      Dim Conn1 As adodb.Connection

      On Error GoTo VbError   ' Trap (non-ADO) error/exceptions

      ' Create Connection Object (using early binding)
      Set Conn1 = new ADODB.Connection

      On Error GoTo AdoError  ' Trap any error/exception

      Conn1.ConnectionString = AccessConnect
      Conn1.Open

      '----------------------
      ' YOUR CODE GOES HERE!
      '----------------------

      ' Successful Shutdown
      Conn1.Close

   Done:
      ' Miscellaneous (graceful) Cleanup
      On Error Resume Next

      Set Conn1 = Nothing

      Exit Sub

   ' ADO Error/Exception Handler
   AdoError:
      ' Save Error Information!
      ErrNumber = Err.Number
      ErrSource = Err.Source
      ErrDescription = Err.Description

      AdoErrorEx List1, Conn1

   ' Non-ADO Native error/exception handler
   VbError:
      VbErrorEx List1, ErrNumber, ErrSource, ErrDescription
      GoTo Done

   End Sub
				

NOTES:

• When using ADOVB with ADO 2.0 or later, you should remove the Reference to Microsoft OLE DB ActiveX Data Objects 1.0, and set a Reference to the latest version of Microsoft ActiveX Data Objects available.
• When using ADO 2.0 or later, referencing the OriginalValue property of an ADO Field object will give the following error, if the LockType of the ADO Recordset is Read Only:
  Run-time error '3251': The operation requested by the application is not supported by the provider.
  To avoid this error in ADOVB, comment out or remove the following line of code, in the Click event procedure for cmdAccess in the code window for frmADOVB:

  List1.AddItem vbTab & "OriginalValue= " & rs1.Fields(i).OriginalValue