using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Reflection;

namespace ConsoleApp4
{

    static class Program
    {
        public static DB EnumObj { get; set; }
        static void Main(string[] args)
        {
            var aaa = EnumObj.Split();
            var bbb = (DB)7;
            var ccc = (DB)15;

            //遍历枚举
            foreach (DB enum2 in Enum.GetValues(typeof(DB)))
            {
                //enum2 = DB.Read;
                var Int = (int)enum2;
                var Str = enum2.ToString();
                var Description = GetDescriptionByEnum(enum2);
            }
            Console.ReadKey();
        }

        // Flags 可以让枚举值以枚举值之和形式提现。有一个前提：（int）大的枚举值必须大过其小于此值枚举值之和
        //比如：ReadWrite > None + Write + Read
        [Flags]
        public enum DB
        {
            None = 0,
            Write = 1,
            [Description("写")]
            Read = 2,
            ReadWrite = 4,
            Max = 8
        }
        //枚举、字符串、数字相互转换
        public static int EnumConvertToInt(DB db) => (int)db;
        public static string EnumConvertToString(DB db) => db.ToString();
        public static DB StringConvertToEnum(string str) => (DB)Enum.Parse(typeof(DB), str);
        public static DB IntConvertToEnum(int i) => (DB)i;
        // 将枚举转化为IEnumerable列表
        public static IEnumerable<T> Split<T>(this T enums) => Enum.GetValues(enums.GetType()).Cast<T>();

        /// <summary>
        /// 获取枚举的 Description 值
        /// </summary>
        /// <param name="enumValue"></param>
        /// <returns></returns>
        public static string GetDescriptionByEnum(Enum enumValue)
        {
            string value = enumValue.ToString();
            FieldInfo field = enumValue.GetType().GetField(value);
            //获取描述属性  
            object[] objs = field.GetCustomAttributes(typeof(DescriptionAttribute), false);
            //当描述属性没有时，直接返回名称
            return objs.Length == 0 ? value : ((DescriptionAttribute)objs[0]).Description;
        }
    }
}