using System;using System.Reflection;using System.Collections;using System.Collections.Generic;namespace AttributeMeta{    [AttributeUsage(AttributeTargets.Field | AttributeTargets.Enum)]    public class EnumDescription : Attribute    {        private FieldInfo fieldInfo;        public EnumDescription(string text, int rank)        {            this.Text = text;            this.Rank = rank;        }        /// 
        /// 描述枚举值，默认排序为5        /// 
        /// 描述内容        public EnumDescription(string text)            : this(text, 5) { }        public string Text { get; set; }        public int Rank { get; set; }        public int Value        {            get            {                return (int)fieldInfo.GetValue(null);            }        }        public string FieldName        {            get            {                return fieldInfo.Name;            }        }        #region 对枚举描述属性的解释相关函数        /// 
        /// 排序类型        /// 
        public enum SortType        {            /// 
            ///按枚举顺序默认排序            /// 
            Default,            /// 
            /// 按描述值排序            /// 
            DisplayText,            /// 
            /// 按排序熵            /// 
            Rank        }        private static Hashtable cachedEnum = new Hashtable();        /// 
        /// 得到对枚举的描述文本        /// 
        /// 枚举类型        /// 
             public static string GetEnumText(Type enumType)        {            EnumDescription[] eds = (EnumDescription[])enumType.GetCustomAttributes(typeof(EnumDescription), false);            if (eds.Length != 1) return string.Empty;            return eds[0].Text;        }        /// 
        /// 获得指定枚举类型中，指定值的描述文本。        /// 
        /// 枚举值，不要作任何类型转换        /// 
     
      描述字符串
             public static string GetFieldText(object enumValue)        {            EnumDescription[] descriptions = GetFieldTexts(enumValue.GetType(), SortType.Default);            foreach (EnumDescription ed in descriptions)            {                if (ed.fieldInfo.Name == enumValue.ToString())                    return ed.Text;            }            return string.Empty;        }        /// 
        /// 得到枚举类型定义的所有文本，按定义的顺序返回        /// 
        /// 
             /// 枚举类型        /// 
     
      所有定义的文本
             public static EnumDescription[] GetFieldTexts(Type enumType)        {            return GetFieldTexts(enumType, SortType.Default);        }        /// 
        /// 得到枚举类型定义的所有文本        /// 
        /// 
             /// 枚举类型        /// 指定排序类型        /// 
     
      所有定义的文本
             public static EnumDescription[] GetFieldTexts(Type enumType, SortType sortType)        {            EnumDescription[] descriptions = null;            //缓存中没有找到，通过反射获得字段的描述信息            if (cachedEnum.Contains(enumType.FullName) == false)            {                FieldInfo[] fields = enumType.GetFields();                ArrayList edAL = new ArrayList();                foreach (FieldInfo fi in fields)                {                    object[] eds = fi.GetCustomAttributes(typeof(EnumDescription), false);                    if (eds.Length != 1) continue;                    ((EnumDescription)eds[0]).fieldInfo = fi;                    edAL.Add(eds[0]);                }                cachedEnum.Add(enumType.FullName, (EnumDescription[])edAL.ToArray(typeof(EnumDescription)));            }            descriptions = (EnumDescription[])cachedEnum[enumType.FullName];            if (descriptions.Length <= 0) throw new NotSupportedException("枚举类型[" + enumType.Name + "]未定义属性EnumValueDescription");            //按指定的属性冒泡排序            for (int m = 0; m < descriptions.Length; m++)            {                //默认就不排序了                if (sortType == SortType.Default) break;                for (int n = m; n < descriptions.Length; n++)                {                    EnumDescription temp;                    bool swap = false;                    switch (sortType)                    {                        case SortType.Default:                            break;                        case SortType.DisplayText:                            if (string.Compare(descriptions[m].Text, descriptions[n].Text) > 0) swap = true;                            break;                        case SortType.Rank:                            if (descriptions[m].Rank > descriptions[n].Rank) swap = true;                            break;                    }                    if (swap)                    {                        temp = descriptions[m];                        descriptions[m] = descriptions[n];                        descriptions[n] = temp;                    }                }            }            return descriptions;        }        /// 
        /// 获得枚举类型数据的列表        /// 
        /// 枚举类型        /// 
     
      Meta 列表
             public static List
      GetMeta(Type enumType)        {            List
      list = new List
     ();            FieldInfo[] fields = enumType.GetFields();            foreach (FieldInfo fi in fields)            {                object[] eds = fi.GetCustomAttributes(typeof(EnumDescription), false);                if (eds.Length != 1)                    continue;                ((EnumDescription)eds[0]).fieldInfo = fi;                var item = eds[0] as EnumDescription;                Meta meta = new Meta                {                    MetaName = item.FieldName,                    MetaRank = item.Rank,                    MetaText = item.Text,                    MetaValue = item.Value                };                list.Add(meta);            }            return list;        }        /// 
        /// 返回枚举类型数据的哈希表        /// 
        /// 枚举类型        /// 
     
      Hashtable
             public static Hashtable GetMetaTable(Type enumType)        {            Hashtable table = new Hashtable();            FieldInfo[] fields = enumType.GetFields();            foreach (FieldInfo fi in fields)            {                object[] eds = fi.GetCustomAttributes(typeof(EnumDescription), false);                if (eds.Length != 1)                    continue;                ((EnumDescription)eds[0]).fieldInfo = fi;                var item = eds[0] as EnumDescription;                table.Add(item.Value, item.Text);            }            return table;        }        /// 
        /// 根据枚举值获得枚举文本        /// 
        /// 枚举类型        /// 枚举值        /// 
     
      Text
             public static object GetMetaValue(Type enumType, int key)        {            object value = null;            Hashtable table = GetMetaTable(enumType);            if (table.Count > 0)            {                value = table[key];            }            return value;        }        /// 
        /// 根据枚举文本获得枚举值        /// 
        /// 枚举类型        /// 枚举文本        /// 
     
      Value
             public static object GetMetaKey(Type enumType, string value)        {            object key = null;            Hashtable table = GetMetaTable(enumType);            if (table.Count > 0)            {                foreach (DictionaryEntry de in table)                {                    if (de.Value.Equals(value))                    {                        key = de.Key;                    }                }            }            return key;        }        #endregion    }    public class Meta    {        public string MetaName { get; set; }        public int MetaValue { get; set; }        public string MetaText { get; set; }        public int MetaRank { get; set; }    }}