Make each csproj in a solution target a different C# version

问题

I have a solution that contains five C# console application projects. I would like each project to target a different version of C#.

MyLearningSolution.sln
    CSharp01.csproj
    CSharp02.csproj
    CSharp03.csproj
    CSharp04.csproj
    CSharp05.csproj

Is there a way to do this either via Visual Studio or via editing each csproj file?

I have tried the following searches:

• csproj target specific C# version, this talks about targeting a specific framework version

• csproj choose c# version, doesn't answer the question

回答1:

This can be done by looking at the <LangVersion> element of the csproj file. Possible values:

<LangVersion>default</LangVersion>
<LangVersion>ISO-1</LangVersion>
<LangVersion>ISO-2</LangVersion>
<LangVersion>3</LangVersion>
<LangVersion>4</LangVersion>
<LangVersion>5</LangVersion>

To do it via the UI, go to Project Properties => Build => Advanced... => Language Version

回答2:

Right click on Project, go to Properites, There under Build click the Advanced.. button, there you can specify Language version.

来源：https://stackoverflow.com/questions/28859651/make-each-csproj-in-a-solution-target-a-different-c-sharp-version