Visual Studio 2010 (maintaining backwards compatibility)

Question

I know in Visual Studio 2008 you can target a specific framework with your projects, but from what I have been told if you open a project originally created in Visual Studio 2003 or 2005 in Visual Studio 2008, it requires you to upgrade the project to a 2008 project to work on it. Does Visual Studio 2010 have this same type of restriction?

It would be very nice being able to use features of 2010 when working in our projects that target different frameworks, but we do not want to force all of our developers to upgrade in order to continue working in these projects.

Answer 1

When you open a VS2008 project with new VS2010 it ask for a project conversion. If not all people involved in the development has the new version you can create 2 SLN files like:

• MySolutionVS2008
• MySolutionVS2010

The project format is the same. The only drawback is that when you need to add a subproject you have to do it manually in both solutions.

The only difference inside is:

Microsoft Visual Studio Solution File, Format Version 11.00
# Visual Studio 2010

Microsoft Visual Studio Solution File, Format Version 10.00
# Visual Studio 2008

Of course in that scenario you cannot use all the new features provided by new language release and framework, to maintain the backward compatibility. But you can use the more productive Intellisense, the improved XAML/WPF designer, etc.

Answer 2

This is not a restriction on multi-targeting. It's a restriction on multiple versions of Visual Studio operating on the same projects.

Yes, you'll have to upgrade the project files. This is why it's best for all developers within an organization to switch over at the same time.

This in no way restricts multi-targeting.