Conditional compilation depending on compiler version

Question

I'm looking for a way to implement something like this:

#if CSHARP_COMPILER_IS_FOR_CSHARP_6_OR_HIGHER
    foo?.Bar();
#else
    if (foo != null)
    {
        foo.Bar();
    }
#endif

Of course, I could define a conditional compilation symbol by myself, but it isn't suitable.

Is there any built-in constant?
The questions I found are rather old. Maybe, the things were changed to the best?

Answer 1

No, from what I know they didn't change anything :-)

You could perhaps do a little magic inside the csproj to define the constants... but it is complex...

There is no property that specifies directly the version of the CSC... There is a property ($(LangVersion)) that specifies the version of the language standard required... but it is normally set to default so "the maximum the compiler supports"...

Or you could look at the path of the CSC compiler... It is stored in the CscToolPath or, if that is empty, in the MsBuildToolsPath. From there perhaps you can discern the version of the CSC.