To ease the pain of converting line after line after line of Visual Basic 6 code to VB 2005, Microsoft provides developers with the Visual Basic Upgrade. The tools works very well Bill Sempf reported in a March 2006 MSDN article, Deconstructing the Visual Basic Upgrade Wizard -- Sempf reports a 96% line-by-line success rate for the programs he tested.
The wizard, though, is not perfect, and Sempf uses the tip to point out what sort of things won't be able to make the move.
For starters, the Upgrade Wizard does not support ASP to ASP.NET migrations. There's a perfectly good reason why, Sempf said -- the wizard covers VB, and ASP apps are written in VBScript.
In addition, three types of functionality -- data, printing and graphics -- are not updated directly from VB 6, Sempf noted. In the first case, ADO objects are wrapped into something called a Runtime Callable Wrapper. In the second case, the concept of a default printer is moot. In the third case, graphical functionality is moved to a different namespace.
Other possible pitfalls involve Solutions/Projects Groups, whose references should be set up before running the Upgrade Wizard and a couple controls that Sempf said did not upgrade properly.
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