Downgrading solution from Visual Studio 2017 RC to Visual Studio 2015

Question

I have had a project in VS 2015 Update 3 with a lot of code logic behind. I upgraded it to VS 2017 RC successfully. The code implementation went on and on until getting to the point where VS 2017 RC exhibited a lot of issues and instabilities eg .Net Core DLL template removed! by installer or Resource file could not be compiled and so forth! I'd like to revert the solution back to VS 2015 to keep working flawlessly but it's impossible easily due to a lot of code implemented in VS 2017 excluding new Roslyn features. Any suggestions how to perform the downgrade?

Answer 1

You will also need to update your *.vcxproj files, to change the toolset referenced there to the one used by the earlier compiler. What I found useful, is to create a small scratch project (just simple console app) in each version of visual studio, then use beyond compare or similar to contrast the .sln and .vcxproj files from each vs version. This will show you the toolset changes and maybe a few others that you need. For example going from vs 2017 to vs 2019 the toolset changes from 141 to 142. So the lines <PlatformToolset>v141</PlatformToolset> are for vs2017 and

<PlatformToolset>v142</PlatformToolset> is for vs2019

Answer 2

这确实是一个手动过程，没有任何工具可以自动化。

Answer 3

I had the same problem and i fixed it using this solution: 1) create a solution of whichever project you want (winforms, etc) 2) browse to your project folder and find your .sln file. 3) open it using notepad. 4) copy the first 4 lines as shown here .

5) find your .sln file for the project you wish to downgrade. for example : foo.sln (its found where your project is). 6) open it with notepad and paste the lines instead of the first 4 lines 7) save and open the sln. it should open it under visual studio 2015

i hope this works for you