如何在Visual Studio 2008中打开和编译.net 4.5 Winform应用程序

Question

I have developed a program in visual studio 2012, my targeting framework was 4.5 and now i want it to be open in vs 2008. I tried to edit cs file in notepad and edited it, but could not compile. Is there any workaround? Any help will be highly appreciated.

Answer 1

Visual Studio 2008 doesn't support the .NET 4.5 Framework. The maximum it supports is 3.5.

Similarly, the maximum VS 2010 supports is .NET 4.0.

You can try changing the target framework to 3.5 before opening it in VS2008, but if you're using anything from the newer frameworks, it won't compile.

Additionally, here's a Wikipedia article with the supported framework (and other information) for each Visual Studio release.

Answer 2

From ScottGu's blog: http://weblogs.asp.net/scottgu/archive/2009/08/27/multi-targeting-support-vs-2010-and-net-4-series.aspx

There isn't any way to target .NET 4 from VS08 and use new features. Having said that, .NET4 is upwards comaptible with .NET 3.5 - so applications you build targeting .NET 3.5 with VS08 should work fine on top of .NET 4.

So in simple words you just can not!

Answer 3

Are you actually using features from the 4.5 framework? There's no IDE-supported way to do this, as other answerers have pointed out. What you can do is this:

1. Create a new project in Visual Studio 2008.
2. Add your files to it.
3. Go through and remove any references to .NET 4.5 and ensure it builds cleanly under .NET 2.0 or whatever VS2008-compatible framework you're targeting.
4. Rinse and repeat until you get a clean build.

Depending on what you're actually using in code, this may entail a lot of work or very little.