What's new in C# 11

 The following features were added in C# 11:

1. Raw string literals
2. Generic math support
3. Generic attributes
4. UTF-8 string literals
5. Newlines in string interpolation expressions
6. List patterns
7. File-local types
8. Required members
9. Auto-default structs
10. Pattern match Span<char> on a constant string
11. Extended nameof scope
12. Numeric IntPtr
13. ref fields and scoped ref
14. Improved method group conversion to delegate
15. Warning wave 7 

Generic Attributes:

// Before C# 11: Old feature

public class TypeAttribute : Attribute

{

   public TypeAttribute(Type t) => ParamType = t;

   public Type ParamType { get; }

}

 

And to apply the attribute, you use the typeof operator:

 [TypeAttribute(typeof(string))]

public string Method() => default;

 

// C# 11 feature: New feature

public class GenericAttribute<T> : Attribute { }

 

Then, specify the type parameter to use the attribute:

[GenericAttribute<string>()]

public string Method() => default;