Q177592: PRB: User Connection Object Connect Property Remains Populated

Article: Q177592
Product(s): Microsoft Visual Basic for Windows
Version(s): 
Operating System(s): 
Keyword(s): kbGrpDSVBDB
Last Modified: 09-JAN-2000

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The information in this article applies to:

- Microsoft Visual Basic Enterprise Edition for Windows, versions 5.0, 6.0 
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SYMPTOMS
========

When a UserConnection object is declared at the global level, the userid and
password stored in the Connect property remains populated after the connection
is closed.

RESOLUTION
==========

To make sure the userid and password in Connect property is cleared after
closing the connection, you can set the user connection object to Nothing right
after closing the connection, such as:

  uc.close
  SET uc = Nothing

You could also store the initial value of the Connect property to a variable, and
replace the Connect property with that value after the connection is closed,
such as the following:

  Dim myConnect As String
  myConnect = uc.Connect
  uc.EstablishConnection
  uc.Close
  uc.Connect = myConnect

STATUS
======

Microsoft is researching this problem and will post new information here in the
Microsoft Knowledge Base as it becomes available.

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

Steps to Reproduce Behavior
---------------------------

Task 1: Create the UserConnection
---------------------------------

1. Start a new project in Visual Basic and choose "Standard EXE." Form1 is
  created by default.

2. From the Project menu, select Components, select the Designers tab, and then
  place a check next to Microsoft UserConnection.

3. From the Project menu, select Add ActiveX Designer, and then select Microsoft
  UserConnection. This will bring up a dialog titled "UserConnection1
  Properties."

4. On the Connection tab, select either a DSN or DSN-less connection and fill in
  the appropriate information. On the Authentication tab, leave User Name and
  Password blank. At ODBC Prompt Behavior dropdown box, choose "Only when
  needed."

5. Click OK to save this information and return to the Designer window.

Task 21: Build the Visual Basic Code
------------------------------------

1. Add two CommandButtons, Command1 and Command2, to Form1. Command1 establishes
  the connection; Command2 closes it Both display the Connect property in the
  debug window.

2. Paste the following code in the General Declaration section of Form1:

        ' *** To workaround the problem:
        ' *** Uncomment the 2 lines of VB code to re-set
        ' *** Connect property using variable myConnect
        ' ***

        Dim uc As New UserConnection1
        Dim myConnect As String

        Private Sub Command1_Click()
           '  myConnect = uc.Connect
           Debug.Print uc.Connect
           uc.EstablishConnection
        End Sub

        Private Sub Command2_Click()
           uc.Close
           '  uc.Connect = myConnect
           Debug.Print uc.Connect
        End Sub

        Private Sub Form_Load()
           Command1.Caption = "Establish Connection"
           Command2.Caption = "Close Connection"
        End Sub

        Private Sub Form_Unload(Cancel As Integer)
           Set uc = Nothing
        End Sub

3. Press F5 key to start the program.

NOTE: Because the userid and password remain populated in the Connect property
after closing the connection, you are only prompted once for the authentication
information after the first connection is established.

REFERENCES
==========

For additional information about User Connection Designer, please see the
following article in the Microsoft Knowledge Base:

  Q166281 HOWTO: Create and Implement a UserConnection

(c) Microsoft Corporation 1997, All Rights Reserved. Contributions by Adrian
Chiang, Microsoft Corporation


Additional query words: kbVBp500 kbVBp600 kbdse kbDSupport kbVBp

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Keywords          : kbGrpDSVBDB 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVB500 kbVB600
Issue type        : kbprb

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