I'm a s/w consultant and having built a 300K LOC mechanical design program over the last several years, my client wants me to migrate it off VB6.

So far, I'm armed with four new WROX books, Rod Stephens' VB 2010 Programmers Reference and VB Graphics Programming, Trearon Willis' Beginning VB 2010 and Danijel Arsenovski's Professional Refactoring in Visual Basic. And from reading this forum I think I'll get Professional Visual Basic 2010 and .net 4 for help with vb.net Database programming.

I've spent three days searching the web for VB migration ideas, learned a lot but I still have some high level questions before I start migration. If any of you have worked on a large VB6 migration, I'd really appreciate your inputs.

Questions:

Until I'm sure I want to migrate to VB.NET, can I get started using the free Upgrade Wizard from VB 2008 Express and then move VB 2010 Express.

Have you seen successful migrations of this size (300K LOC) done with Microsoft's Upgrade Wizard followed by "Refactoring" or do people seem to rely on migration services from companies like ArtinSoft or Code Architects. Do you know of off-shore providers that have provided good migration service?

Two attributes of my program I should mention are 1. there's a great deal of 2D graphics (drawing mechanical components) and 2. there are many, many DAO calls to an Access dB. Is Rod Stephens' VB Graphics Programming the best reference for my graphics migration? Is Professional Visual Basic 2010 and .net 4 the best reference for DAO migration?

Is it possible to combine VB6 modules with VB.net so that I can migrate over time and allow users to run a partially migrated project?

Finally, I know this answer "depends" but how many man-months of programming did it take you for your VB6 migration(s). How many lines of code?

Thanks,
Dick

If it were my product I would NOT try to migrate the old code. I would start over with VB 2010. I would also even consider using SQL Server Express as the back end.

I see not migration when you switch to VB.NET as a great opportunity to really take your app forward.

__________________
Boyd Trimmell aka HiTechCoach (.com)
Microsoft Access MVP Alumni 2010-2015

I am currently in the same boat! I have been a VB programmer since VB3. Switching over after using the same basic language (pardon the pun) for about 15 years can be a brain-busting journey. I am happy to say that I have come a long way in a short time....

I suggest this: Take it a portion of your application at a time, based on function, and then learn to write code in VB.NET to perform the same functions. You mention ACCESS database code. Just create an application that loads, saves, updates the data... You mentioned 2D Drawings. Make an application that performs similar drawing functions... Learn it one function at a time, then apply these building blocks into your NEW VERSION...

You can import VB6 projects into VB.NET and it will convert all it can. It then gives you a list of what it could not convert. The problem I see for you is.... Database and Drawing (graphics) are the things it won't convert due to the HUGE changes .NET has for those.

Good luck!

Even though this is an old post, this problem is not going away. I personally have dealt with migrating software for many years. I have done it either by hand, or using custom tools I wrote. Either way it took a long time to get it near complete. When doing migrations I now use this companies tool http://www.greatmigrations.com/. I have to say, it fast and fully configurable. Unlike other tools out there, it gets the code to 100% and over using the migration rules and configuration settings. I used it on a project of mine, and completed it in no time. I highly recommend using this tool.