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Q257714: FIX: ADODC and DataEnvironment Events Only Work with ADO 2.0

Article: Q257714
Product(s): Microsoft Visual Basic for Windows
Version(s): WINDOWS:2.0,2.01,2.1,2.1 SP1,2.1 SP2,2.5,6.0
Operating System(s): 
Keyword(s): kbCtrl kbDatabase kbDataBinding kbDesigner kbMDAC kbVBp600bug kbDataEnv kbGrpDSVBDB kbG
Last Modified: 23-AUG-2001

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The information in this article applies to:

- Microsoft Visual Basic Professional Edition for Windows, version 6.0 
- Microsoft Visual Basic Enterprise Edition for Windows, version 6.0 
- ActiveX Data Objects (ADO), versions 2.0, 2.01, 2.1, 2.1 SP1, 2.1 SP2, 2.5, 2.5 SP2, 2.7 
-------------------------------------------------------------------------------

SYMPTOMS
========

When you attempt to use the events of an ADO Data Control or the DataEnvironment
with a reference to a version of the Microsoft ActiveX Data Objects (ADO) later
than version 2.0, you receive the following error message:

  Compile error:
  Procedure declaration does not match description of event or procedure having
  the same name.

CAUSE
=====

The ADO Data Control and the Data Environment were compiled using Microsoft Data
Access Components version 2.0.

RESOLUTION
==========

This problem no longer occurs with the ADO Data Control and the Data Environment
that ship with Microsoft Visual Studio Service Pack 4 and later.

However, you must now use a reference to the Microsoft ActiveX Data Objects 2.5
Library or later if you are using ADO Data Control and Data Environment events.
The ADO Data Control and the Data Environment have been recompiled using
Microsoft Data Access Components 2.5. That is, you now see the preceding error
message when using the ADO Data Control or the Data Environment with a reference
to a version of Microsoft Data Access Components prior 2.5.

In short, when using the events of the ADO Data Control or the Data Environment
in Microsoft Visual Basic 6.0 Service Pack 4, be sure to do the following:

1. From the Project menu, clink to select References.

2. From the list of available References, deselect references to Microsoft
  ActiveX Data Objects prior to version 2.5.

3. From the list of available References, select Microsoft ActiveX Data Objects
  2.5 or later.

For versions of Visual Studio prior to service pack 4, the workaround is to add
"20" to the ADODB.Recordset Parameter declaration, as described in the articles
listed in the "References" section of this article. IMPORTANT: The workaround as
described in Q222145 does not work with Visual Studio 6.0 Service Pack 4. The
code needs to be changed to use the original declarations for each of the events
(20 needs to be removed from the Recordset Parameter declaration).


STATUS
======

Microsoft has confirmed that this is a bug in the Microsoft products that are
listed at the beginning of this article. This bug was corrected in the latest
service pack for Visual Studio 6.0.

For additional information about Visual Studio service packs, click the following
article numbers to view the articles in the Microsoft Knowledge Base:

  Q194022 INFO: Visual Studio 6.0 Service Packs, What, Where, Why

  Q194295 HOWTO: Tell That a Visual Studio Service Pack Is Installed

To download the latest Visual Studio service pack, visit the following Microsoft
Web site:

  http://msdn.microsoft.com/vstudio/downloads/updates.asp

MORE INFORMATION
================

Steps to Reproduce Behavior Using ADO Data Control
--------------------------------------------------

This sample uses an ODBC Datasource named Nwind that connects to the Nwind
database that comes with Visual Studio.

1. In Visual Basic, create a new Standard EXE project. Project1 is created by
  default. Form1 is added by default.

2. From the Project menu, click to select Components. From the list of available
  Components, select Microsoft ADO Data Control (OLEDB).

3. Place an ADO Data Control and a TextBox onto Form1. ADODC1 and Text1 are
  created by default.

4. Set the following properties of ADODC1:

   - ConnectionString: DSN=NWind

   - RecordSource: Select * from Employees

5. Set the following properties of Text1:

   - DataSource: ADODC1

   - DataField: FirstName

6. From the Project menu, click to select References. From the list of
  References, deselect Microsoft ActiveX Data Objects 2.0 Library. From the
  list of available References, click to select Microsoft ActiveX Data Objects
  2.1 Library or later.

7. Paste the following code into Form1's code window:

  Private Sub Adodc1_WillMove(ByVal adReason As ADODB.EventReasonEnum,
  adStatus As ADODB.EventStatusEnum, ByVal pRecordset As ADODB.Recordset)
    MsgBox "Hello"
  End Sub

8. Run the program and note that you see the error message from the "Symptoms"
  section in the WillMove event.

Steps to Reproduce Behavior, Using DataEnvironment
--------------------------------------------------

This sample uses an ODBC Datasource named Nwind that connects to the Nwind
database that comes with Visual Studio.

1. In Visual Basic, create a new Standard EXE project. Project1 is created by
  default. Form1 is added by default.

2. From the Project menu, click to select Add Data Environment. DataEnvironment1
  is added by default. The DataLink Properties window is opened by default.

  a. On the Provider tab, select Microsoft OLE DB Provider for ODBC Drivers.
     Click Next.

  b. On the Connection tab, select Use data source name. From the list of
     available ODBC data source names, select Nwind. Click Test Connection.
     Click OK, and then click OK again.

3. In the DataEnvironment1 (DataEnvironment) window, right-click on Connection1.
  From the pop-up menu, select Add Command.

  a. Change the Database Object from Stored Procedure to Table.

  b. From the Object Name list, select Customers.

  c. Click OK. Command1 is created by default.

4. Drag Command1's icon from the DataEnvironment window onto Form1 and release.
  Note that Labels and Textboxes representing the fields of the Command object
  are placed on the form. You do not need to further modify the placement or
  properties of the Labels and Textboxes.

5. From the Project menu, click to select References. From the list of
  References, deselect Microsoft ActiveX Data Objects 2.0 Library. From the
  list of available References, click to select Microsoft ActiveX Data Objects
  2.1 Library or later.

6. In the DataEnvironment window, double-click on DataEnvironment1 to open its
  Code window. Paste the following code into DataEnvironment1's Code window:

  Private Sub rsCommand1_WillMove(ByVal adReason As ADODB.EventReasonEnum,
  adStatus As ADODB.EventStatusEnum, ByVal pRecordset As ADODB.Recordset)
    MsgBox "Hello"
  End Sub

7. Run the project, and note that the error message in the "Symptoms" section
  appear in the WillMove event.

REFERENCES
==========

  Q222145 PRB:ADO Data Control Events May Generate a Compilation Error

  Q193326 BUG:Data Form Wizard via Application Wizard Omits ADO Reference

Additional query words: sp4

======================================================================
Keywords          : kbCtrl kbDatabase kbDataBinding kbDesigner kbMDAC kbVBp600bug kbDataEnv kbGrpDSVBDB kbGrpDSMDAC kbDSupport kbVS600sp4fix kbVS600sp5fix kbATM kbmdac270 kbado270 
Technology        : kbVBSearch kbAudDeveloper kbADOsearch kbADO210 kbADO201 kbADO200 kbADO210sp1 kbADO210sp2 kbADO250 kbZNotKeyword6 kbZNotKeyword2 kbVB600Search kbVB600 kbADO270
Version           : WINDOWS:2.0,2.01,2.1,2.1 SP1,2.1 SP2,2.5,6.0
Issue type        : kbbug
Solution Type     : kbfix

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