I tried installing .net framework 4.7.2, still the target framework is empty in the project properties. The program I'm trying to run uses readonly struct, which is part C# 7.2.
Could you please guide me .Net Framework version has C# 7.2?
Language features are independent of .Net version (Framework/Core/Standard).
You will need to use a compiler that understands the newer language features. Assuming you're using Visual Studio 2017, you should update to latest version.