How Does Resharper's 'Enabled C# 6.0 Features' Work in Visual Studio 2012?

Question

I've been told that C# 6.0 is not going to be supported by Visual Studio 2012 and that to compile C# 6.0 code, I would need to upgrade to a newer version of Visual Studio.

However, when I paste in C# 6.0 code, Resharper asks me if I would like to enable C# 6.0 support. If I allow it, I'm able to compile C# 6.0 code.

        List<string> customers = null;
        string Customer;

        int? length = customers?.Count; 
        Customer = customers?[0];      

It seems to work, but can anyone explain how it's working?

If I go into the project's properties / Build / Advanced... the 'Language version' is set to 'default'. And if I check the dropdown, I can only see up to C# 5.0.

Answer 1

根据此答案 ，如果您在项目中安装了“ Microsoft.Net.Compilers” NuGet软件包，则它可以在VS 2012中工作。

Answer 2

我最好的猜测是您正在使用ReSharper Build Engine（ReSharper->选项->工具-> Build，请参阅Build Engine）