C# 8.0 adds the following features and enhancements to the C# language:
Readonly members
Default interface members
Pattern matching enhancements:Switch expressions
Property patterns
Tuple patterns
Positional patterns
Using declarations
Static local functions
Disposable ref structs
Nullable reference types
Asynchronous streams
Indices and ranges
Null-coalescing assignment
Unmanaged constructed types
stackalloc in nested expressions
Enhancement of interpolated verbatim strings
Read more: https://docs.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-8
