Cannot Use VBScript Classes with Application or Session Scope

ID: Q246596

The information in this article applies to:

Microsoft Internet Information Services version 5.0

SYMPTOMS

The VBScript 5.0 engine allows the creation of user defined classes, similar to the Visual Basic classes.

When you attempt to assign a class as an Application variable, the following error message occurs:

Error Type:
Application object, ASP 0197 (0x80004005)
Disallowed object use
Cannot add object with apartment model behavior to the application intrinsic object.
/<path>/<file.ext>, line <nn>

In addition, when you assign a class to a Session variable, the following error message occurs when you attempt to use the class:

Error Type:
Microsoft VBScript runtime (0x800A01B6)
Object doesn't support this property or method: <class variable>
/<path>/<file.ext>, line <nn>

CAUSE

This behavior is by design. There are specific threading issues that prevent this functionality from being exposed at the Application or Session level.

RESOLUTION

Only use VBScript classes with page-level scope.

WORKAROUND

To work around this issue, use Include files to store VBScript classes. To do this perform the following steps:

Save the following ASP code as Convert.inc in a folder with at least Script access:


<%
Class Convert
	Function Celsius(F)
		Celsius = ((F-32)*5)/9
	End Function
	Function Fahrenheit(C)
		Fahrenheit = ((C*9)/5)+32
	End Function
End Class
%>

Save the following ASP code as Convert.asp in the same folder as the above file:


<% @LANGUAGE="VBSCRIPT" %>
<!--#include file="class.inc"-->
<% Set MyConvert = New Convert %>
<html>
<body>
<pre>32F = <%=MyConvert.Celsius(32)%>C</pre>
<pre>32C = <%=MyConvert.Fahrenheit(32)%>F</pre>
</body>
</html>

When you browse the Convert.asp page, the following should be returned:
```
32F = 0C
32C = 89.6F 
```

Note: The above example does not preserve class state between pages. In other words, if any variables are created in the class, they will be destroyed when the page goes out of scope.

MORE INFORMATION

For more information on Microsoft Scripting Technologies, please see the Microsoft Developer Network (MSDN) Web site at the following URL:

http://msdn.microsoft.com/scripting/

Note: Microsoft provides programming examples for illustration only, without warranty either expressed or implied, including, but not limited to, the implied warranties of merchantability and/or fitness for a particular purpose. This article assumes that you are familiar with the programming language being demonstrated and the tools used to create and debug procedures. Microsoft support professionals can help explain the functionality of a particular procedure, but they will not modify these examples to provide added functionality or construct procedures to meet your specific needs. If you have limited programming experience, you may want to contact a Microsoft Certified Solution Provider or the Microsoft fee-based consulting line at (800) 936-5200. For more information about Microsoft Certified Solution Providers, please see the following page on the World Wide Web:

http://www.microsoft.com/mcsp/

For more information about the support options available from Microsoft, please see the following page on the World Wide Web:

http://www.microsoft.com/support/supportnet/overview/overview.asp

Additional query words:

Keywords : kbWinOS2000
Version : winnt:5.0
Platform : winnt
Issue type : kbprb