How to Use ADO with Visual Basic

ID: Q172403

The information in this article applies to:

ActiveX Data Objects (ADO), versions 1.5, 2.0, 2.1 SP2
Microsoft Visual Basic Professional Edition for Windows, versions 5.0, 6.0

SUMMARY

Adovb.exe is a self-extracting compressed file containing sample code that demonstrates how to use ActiveX Data Objects (ADO) within Visual Basic.

MORE INFORMATION

The following file is available for download from the Microsoft Download Center. Click the file name below to download the file:

AdoVB.EXE

For more information about how to download files from the Microsoft Download Center, please visit the Download Center at the following Web address

http://www.microsoft.com/downloads/search.asp

and then click How to use the Microsoft Download Center.

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 
```

REFERENCES

About the ADO* Series of Samples

This is one of several identical samples implemented using ADO within various products, as listed below. The advantage is that these articles have an identical interface/functionality, demonstrating both the similarities and differences in using ADO with different languages / mechanisms:

Q172403 FILE: Adovb.exe Demonstrates How to Use ADO with Visual Basic

Q220152 Sample: ADOVC1 Simple ADO/VC++ Application

Q182782 FILE: Adovj.exe Demonstrates How to Use ADO with Visual J++

Q185033 FILE: Adoacc.exe Demonstrates Using ADO with Access 97

Additional query words:

Keywords : kbcode kbfile kbsample kbADO kbADO200 kbDatabase kbSQLServ kbStoredProc kbVBp kbVBp500 kbVBp600 kbGrpVBDB kbGrpMDAC kbDSupport kbADO210sp2
Version : WINDOWS:1.5,2.0,2.1 SP2,5.0,6.0
Platform : WINDOWS
Issue type : kbinfo