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

• Active Server Pages
• Microsoft Visual Basic Learning, Professional, and Enterprise Editions for Windows, versions 5.0, 6.0

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

1. Create a Visual Basic ActiveX DLL project called VBUDTPrj.



2. Add class module called VBUDTObj.



3. Define a UDT as follows:

   Public Type TestUDT
      strName as String
      strDept as String  
   End Type 




4. Implement the following method:

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




5. 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>" )
   %> 




6. 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.

Additional query words:

Keywords          : kbsample kbASP kbASP400 kbCOMt kbVBp500 kbVBp600 kbGrpASP 
Version           : WINDOWS:5.0,6.0; winnt:
Platform          : WINDOWS winnt 
Issue type        : kbprb 

Last Reviewed: May 25, 1999