using System;

​

namespace EnumExtension {

  public static class Extensions {

    public static string japanese(this Seasons season) {

      return season switch {

          Seasons.Spring => "春",

          Seasons.Summer => "夏",

          Seasons.Autumn => "秋",

          Seasons.Winter => "冬",

//          _ => "???",  XXX 網羅性の検証を阻害します

      };

    }

  }

​

  public enum Seasons {

    Spring,

    Summer,

    Autumn,

    Winter,

  }

​

  public class EnumTypeEx {

    public static void Main() {

      var season = Seasons.Summer;

      Console.WriteLine($"{season}({typeof(Seasons)})：{(int)season}  -- {season.japanese()}");

      Console.WriteLine();

      foreach(Seasons s in Enum.GetValues(typeof (Seasons))) {

        Console.WriteLine($"{s}: {s.japanese()}");

      }

    }

  }

}