Q185539: HOWTO: Create a Web Aware UserControl

Article: Q185539
Product(s): Microsoft Visual Basic for Windows
Version(s): 
Operating System(s): 
Keyword(s): kbGrpDSVBDB
Last Modified: 20-FEB-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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SUMMARY
=======

This article covers the creation of a Web-aware Usercontrol that downloads
images from a public site from the Internet.

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

This example shows how you can create controls that are Web-aware:

1. Start Visual Basic and select the ActiveX Control (this creates a Usercontrol
  project) in the New Project dialog box. Add a picture control and a label to
  the Usercontrol project making sure to place the label above the picture
  control. Add the following code:

        Option Explicit
        Const vbAsyncTypePicture = 0

        Private Sub UserControl_AsyncReadComplete(AsyncProp As
        AsyncProperty)
          On Error Resume Next
          Set Picture1.Picture = AsyncProp.Value
        End Sub

        Private Sub UserControl_Initialize()
        'PLEASE NOTE:
        'The URL could be in the form of a shared directory,
        'FTP or a HTTP.  The convention below, is used as
        'an example only. Do not try to use this URL as it is
        'in fact bogus.
         UserControl.AsyncRead _
           "http://example.microsoft.com/example.jpg", _
            vbAsyncTypePicture
        End Sub

2. Add a Caption to the label:

        Label1.Caption = "Image View"

3. Rename the project to something other than Project1 and create the control by
  compiling to an OCX.

4. Start a new standard exe project and add the new control to it. When you
  place the control on the form, the image automatically appears.

You could just as easily add a timer to this project, and use it to change the
image number. You could also use a public variable that would enable your
control to communicate with the form and change the image from outside the
control.

REFERENCES
==========

Visual Basic 5.0 Online Help; search on: "UserControls"

(c) Microsoft Corporation 1998, All Rights Reserved. Contributions by Richard T.
Edwards, Microsoft Corporation


Additional query words: Internet programming kbDsupport KbDSe kbVBp500 kbVBp500 KBiNTERNET

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

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