问题
After installing VS 2015, running csc.exe from command line causes this message to be displayed to console:
This compiler is provided as part of the Microsoft (R) .NET Framework, but only supports language versions up to C# 5, which is no longer the latest version. For compilers that support newer versions of the C# programming language, see http://go.microsoft.com/fwlink/?LinkID=533240
The link redirects to Roslyn's repository at GitHub.
So, is the a way to run "compilers that support newer versions" (Roslyn) from command line?
回答1:
It sounds like your path is inappropriate, basically. If you open the "Developer Command Prompt for VS2015" you should have $ProgramFiles(x86)$\MSBuild\14.0\bin early in your path - and the csc.exe in there is Roslyn.
I suspect you're running the version in c:\Windows\Microsoft.NET\Framework\4.0.30319 or similar - which is the legacy one, basically.
来源：https://stackoverflow.com/questions/31875825/how-to-run-roslyn-instead-csc-exe-from-command-line