Q127029: PRB: Type Mismatch with Default Prop of VB4 Data Access Object

Article: Q127029
Product(s): Microsoft Visual Basic for Windows
Version(s): 
Operating System(s): 
Keyword(s): 
Last Modified: 11-JAN-2001

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The information in this article applies to:

- Microsoft Visual Basic Standard Edition, 32-bit, for Windows, version 4.0 
- Microsoft Visual Basic Professional Edition, 16-bit, for Windows, version 4.0 
- Microsoft Visual Basic Professional Edition, 32-bit, for Windows, version 4.0 
- Microsoft Visual Basic Enterprise Edition, 16-bit, for Windows, version 4.0 
- Microsoft Visual Basic Enterprise Edition, 32-bit, for Windows, version 4.0 
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SYMPTOMS
========

Some data access objects in Visual Basic for Windows version 4.0 no longer have
the default "Name" property. Instead, these objects now have a default
collection. This change can lead to "Type Mismatch" (Error 13) or "Invalid
Argument" (Error 3001) errors when attempting to run your code.

WORKAROUND
==========

To work around this problem, add the name of the property you want to
reference.

For example, use this:

     MsgBox Data1.Database.TableDefs(0).Name

instead of this:

     MsgBox Data1.Database.TablesDefs(0)

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

If a data access object in Microsoft Visual Basic version 4.0 has a collection
as a property, the collection is now the default property. There is no longer
support for default properties on any objects except Field, Parameter and
Property objects.

This is a change in behavior from Microsoft Visual Basic version 3.0 where the
"Name" property was the default property for TableDef object.

Having a default collection allows the user to implement a short hand syntax for
referencing into the collection.

For example, this:

     MsgBox Data1.Database.TableDefs(0).Fields(0).Name

can be written as this:

     MsgBox Data1.Database.TableDefs(0)(0).Name

Additional query words: 4.00 compatibility vb4win vb4all

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Keywords          :  
Technology        : kbVBSearch kbAudDeveloper kbVB400Search kbVB400 kbVB16bitSearch
Issue type        : kbprb

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