How to find what versions of C# and .NET/Mono are being used?

Question

You can use System.Environment.Version to the get the version of the CLR; how do you get the versions of C# and of the .NET or Mono framework currently being used?

EDIT: I am NOT asking how to find whether you are using Mono or .NET. (The very first version of my question did ask that as a secondary question, but I deleted that almost immediately when I saw that question answered elsewhere.) The questions here are (1) how to figure out what version of C# you are working with, and (2) what version of .NET you have (as opposed to the version of the CLR, which isn't the same thing ).

Answer 1

Checking if you're running in mono:

public static bool IsRunningOnMono ()
{
    return Type.GetType ("Mono.Runtime") != null;
}

Checking the mono version:

Type type = Type.GetType("Mono.Runtime");
if (type != null)
{                                          
    MethodInfo dispalayName = type.GetMethod("GetDisplayName", BindingFlags.NonPublic | BindingFlags.Static); 
    if (dispalayName != null)                   
        Console.WriteLine(dispalayName.Invoke(null, null)); 
}

If you're not in Mono, then you still use System.Environment.Version

Answer 2

a very similar question has been asked already:

public static bool IsRunningOnMono ()
{
    return Type.GetType ("Mono.Runtime") != null;
}

How to detect which .NET runtime is being used (MS vs. Mono)?

and for detecting the .NET framework's version currently used at runtime for execution you can check Environment.Version