利用C#实现可以继承的"枚举"

using System;
using System.Collections;
using System.Collections.Generic;
   namespace HeritableEnum
   {
       public class HEnum : IComparable<HEnum>, IEquatable<HEnum>
       {
          static int counter = -1;            //默认数值计数器
         private static Hashtable hashTable = new Hashtable();       //不重复数值集合
         protected static List<HEnum> members = new List<HEnum>();   //所有实例集合
         private string Name { get; set; }
          private int Value { get; set; }
        /// <summary>
         /// 不指定数值构造实例
          /// </summary>
         protected HEnum(string name)
         {
             this.Name = name;
             this.Value = ++counter;
              members.Add(this);
             if (!hashTable.ContainsKey(this.Value))
              {
                 hashTable.Add(this.Value, this);
              }
         }
          /// <summary>
         /// 指定数值构造实例
          /// </summary>
         protected HEnum(string name, int value)
             : this(name)
         {
             this.Value = value;
             counter = value;
          }
          /// <summary>
          /// 向string转换
          /// </summary>
          /// <returns></returns>
          public override string ToString()
         {
              return this.Name.ToString();
          }
         /// <summary>
          /// 显式强制从int转换
          /// </summary>
          /// <param name="i"></param>
          /// <returns></returns>
          public static explicit operator HEnum(int i)
          {
              if (hashTable.ContainsKey(i))
             {
                  return (HEnum)members[i];
             }
             return new HEnum(i.ToString(), i);
          }
          /// <summary>
         /// 显式强制向int转换
         /// </summary>
         /// <param name="e"></param>
          /// <returns></returns>
         public static explicit operator int(HEnum e)
         {
             return e.Value;
          }
         public static void ForEach(Action<HEnum> action)
         {
              foreach (HEnum item in members)
              {
                 action(item);
             }
          }
          public int CompareTo(HEnum other)
          {
             return this.Value.CompareTo(other.Value);
         }
         public bool Equals(HEnum other)
          {
              return this.Value.Equals(other.Value);
          }
          public override bool Equals(object obj)
          {
            if (!(obj is HEnum))
                  return false;
              return this.Value == ((HEnum)obj).Value;
         }
        public override int GetHashCode()
         {
              HEnum std = (HEnum)hashTable[this.Value];
             if (std.Name == this.Name)
                 return base.GetHashCode();
             return std.GetHashCode();
         }
         public static bool operator !=(HEnum e1, HEnum e2)
         {
             return e1.Value != e2.Value;
         }
         public static bool operator <(HEnum e1, HEnum e2)
         {
             return e1.Value < e2.Value;
         }
        public static bool operator <=(HEnum e1, HEnum e2)
         {
             return e1.Value <= e2.Value;
        }
         public static bool operator ==(HEnum e1, HEnum e2)
         {
             return e1.Value == e2.Value;
         }
         public static bool operator >(HEnum e1, HEnum e2)
         {
            return e1.Value > e2.Value;
         }
         public static bool operator >=(HEnum e1, HEnum e2)
         {
             return e1.Value >= e2.Value;
         }
     }
 }

class EnumUse1 : HEnum
{
    protected EnumUse1(string name) : base(name) { }
    protected EnumUse1(string name, int value) : base(name, value) { }
    public static EnumUse1 A = new EnumUse1("A");
    public static EnumUse1 B = new EnumUse1("B", 2);
    public static EnumUse1 C = new EnumUse1("C", 2);
    public static EnumUse1 D = new EnumUse1("D");
}

enum EnumUse1
{
    A,
    B = 2,
    C = 2,
    D
}

class EnumUse2 : EnumUse1
{
    protected EnumUse2(string name) : base(name) { }
    protected EnumUse2(string name, int value) : base(name, value) { }
    public static EnumUse2 E = new EnumUse2("E");
}

class Program
{
    static void Main(string[] args)
    {
        bool b = EnumUse1.D >= EnumUse1.A;
        Console.WriteLine(b.ToString());
        Show(EnumUse2.E);
        HEnum.ForEach((x) => Console.WriteLine("{0} = {1},", x, (int)x));
    }
    static void Show(HEnum e)
    {
        Console.WriteLine(@"{0} = {1},""{2}""", e, (int)e, e.ToString());
    }
}