The title says it all: what CLR version is / will be needed to run C# 6 programs? The CLR version is interesting to find out the system requirements and supported operating systems.
I googled [1] [2] and had a look at Wikipedia and MSDN but could not find the information.
C # 6 language enhancements is compatible to .net framework starting from 2.0 to 4.6. It does not require any higher version of .net framework but need higher version of Visual studio such as VS 2015. C# 6 is also available to VS 2013 with addon https://github.com/dotnet/roslyn
It is version 4 of CLR that is used. If you test Environment.Version in Visual Studio "14" CTPs you will get:
4.0.30319.35317
With code:
Console.WriteLine(Environment.Version);
Also if you look at Common Language Runtime (CLR) on MSDN you will find:
.Net Framework Version CLR Version
4.5 (including 4.5.1 and 4.5.2) 4
In order to have C# 6 you need:
- VS 2013
- Download C# 6 from Codeplex -Roslyn
VS 2013 runs on .NET 4.5.1 so I guess the answer to your Question is 4.5.1
来源：https://stackoverflow.com/questions/23605210/what-clr-is-needed-for-c-sharp-6