C# 写个枚举扩展方法，字符串根据枚举描述值Description转成指定枚举对象

见代码

[TypeConverter(typeof(DescribedEnumConverter<FlatTypeEnum>))]
  public enum FlatTypeEnum
  {
      [Description("N")]
      N,
      [Description("F")]
      F
  }

  public static class EnumExtend<T> where T : Enum
  {
      public static T? GetEnumValueByDescription(string desc)
      {
          foreach (T item in Enum.GetValues(typeof(T)))
          {
              if (GetDescriptionByEnum(item) == desc)
                  return item;
          }
          return default;
      }

      private static string GetDescriptionByEnum(Enum enumValue)
      {
          string value = enumValue.ToString();
          System.Reflection.FieldInfo? field = enumValue.GetType().GetField(value);
          if (field == null)
              return value;
          object[] objs = field.GetCustomAttributes(typeof(DescriptionAttribute), false);    //获取描述属性
          if (objs.Length == 0)    //当描述属性没有时，直接返回名称
              return value;
          DescriptionAttribute descriptionAttribute = (DescriptionAttribute)objs[0];
          return descriptionAttribute.Description;
      }
  }