PRB: Returning a UDT from a VB COM Object Brings an Error (224422)

The information in this article applies to:

Microsoft Active Server Pages
Microsoft Visual Basic Learning Edition for Windows 5.0
Microsoft Visual Basic Learning Edition for Windows 6.0
Microsoft Visual Basic Professional Edition for Windows 5.0
Microsoft Visual Basic Professional Edition for Windows 6.0
Microsoft Visual Basic Enterprise Edition for Windows 5.0
Microsoft Visual Basic Enterprise Edition for Windows 6.0
Microsoft Internet Information Server 4.0
Microsoft Internet Information Server 5.0

This article was previously published under Q224422

SYMPTOMS

When you return a user-defined data type (UDT) from a Visual Basic COM object, you might get one of the following error messages:

Microsoft VBScript runtime error '800a01a8'
Object required

-or-

Response object error 'ASP 0106 : 80020005'
Type Mismatch
?
An unhandled data type was encountered

CAUSE

User-defined data types are not supported in the current version of Active Server Pages (ASP).

RESOLUTION

Active Server Pages does not support UDTs, but you can work around this by creating a new class to handle the data in place of the UDT and setting the instancing property to PublicNotCreateable. This will ensure that you can pass the necessary information to and from ASP, as well as ensuring that the class cannot be created outside of the DLL.

STATUS

This behavior is by design.

MORE INFORMATION

Steps to Reproduce Behavior

Create a Visual Basic ActiveX DLL project called VBUDTPrj.
Add class module called VBUDTObj.

Define a UDT as follows:

Public Type TestUDT
   strName as String
   strDept as String  
End Type

Implement the following method:

Public Function TestMethod() As Variant
    Dim udtTestData As TestUDT
    
    udtTestData.strDept = "TestDept"
    udtTestData.strName = "TestName"
    
    TestMethod = udtTestData    
End Function

Create an ASP page that calls this method:

<%
   Dim objTest, udtData
   Set objTest = Server.CreateObject("VBUDTPrj.VBUDTObj")
   udtData = objTest.TestMethod()

   Response.Write( "Name = " & udtData.strName & "<BR>" )
   Response.Write( "Dept = " & udtData.strDept & "<BR>" )
%>

Run the ASP page. The the following error occurs:
Microsoft VBScript runtime error '800a01a8'
Object required

REFERENCES

See the TYPE statement in the Visual Basic Documentation.

Modification Type:	Minor	Last Reviewed:	7/16/2004
Keywords:	kbCodeSnippet kberrmsg kbprb KB224422