EnumHelper.cs

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

namespace theilgazcode.Utilities
{

    public class EnumItem
    {
        public int Value { get; set; }

        public string Name { get; set; }

        public string Description { get; set; }

    }

    public static class EnumHelper
    {
        /// <summary>
        /// Enum değerine ait açıklama bilgisi döner.
        /// </summary>
        /// <param name="value"></param>
        /// <returns></returns>
        public static string GetDescription(Enum value)
        {
            return
                value
                    .GetType()
                    .GetMember(value.ToString())
                    .FirstOrDefault()
                    ?.GetCustomAttribute<DescriptionAttribute>()
                    ?.Description
                ?? value.ToString();
        }
 
        /// <summary>
        /// Value ve Description değerleri SortedDictionary olarak döner.
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <returns></returns>
        public static SortedDictionary<int, string> GetValues<T>() where T : struct, IConvertible
        {
            if (!typeof(T).IsEnum)
            {
                throw new ArgumentException("Enum tipi gönderilmeli.");
            }

            SortedDictionary<int, string> sortedList = new SortedDictionary<int, string>();
            Type enumType = typeof(T);
            foreach (T value in Enum.GetValues(enumType))
            {
                FieldInfo fi = enumType.GetField(value.ToString());
                DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false);
                if (attributes != null && attributes.Length > 0)
                {
                    DescriptionAttribute description = (DescriptionAttribute)attributes[0];
                    sortedList.Add(value.ToInt32(CultureInfo.CurrentCulture.NumberFormat), description.Description);
                }
                else
                {
                    sortedList.Add(value.ToInt32(CultureInfo.CurrentCulture.NumberFormat), value.ToString());
                }
            }

            return sortedList;
        }

        /// <summary>
        /// Enum değeri parametre geçilerek enum olarak geri döndürür.
        /// 
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="value"></param>
        /// <returns></returns>
        public static T GetEnum<T>(int value) where T : struct, IConvertible
        {
            if (!typeof(T).IsEnum)
            {
                throw new ArgumentException("Enum tipi gönderilmeli.");
            }

            Type enumType = typeof(T);
            var values = Enum.GetValues(enumType);
            foreach (T e in values)
            {
                if (e.ToInt32(CultureInfo.CurrentCulture.NumberFormat) == value)
                {
                    return e;
                }
            }
            return new T();
        }

        /// <summary>
        /// Enum ismi parametre geçilerek enum olarak geri döndürür.
        /// 
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="name"></param>
        /// <returns></returns>
        public static T GetEnum<T>(string name) where T : struct, IConvertible
        {
            if (!typeof(T).IsEnum)
            {
                throw new ArgumentException("Enum tipi gönderilmeli.");
            }

            Type enumType = typeof(T);
            var values = Enum.GetValues(enumType);
            foreach (T e in values)
            {
                FieldInfo fi = enumType.GetField(e.ToString());
                if (fi.Name == name)
                {
                    return e;
                }
            }
            return new T();
        }

        /// <summary>
        /// Enum değeri parametre geçilerek EnumItem olarak geri döndürür.
        /// 
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="value"></param>
        /// <returns></returns>
        public static EnumItem GetItem<T>(int value) where T:struct,IConvertible
        {
            if (!typeof(T).IsEnum)
            {
                throw new ArgumentException("Enum tipi gönderilmeli.");
            }

            Type enumType = typeof(T);
            foreach (T e in Enum.GetValues(enumType))
            {
                if (e.ToInt32(CultureInfo.CurrentCulture.NumberFormat) == value)
                {
                    FieldInfo fi = enumType.GetField(e.ToString());
                    DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false);
                    if (attributes != null && attributes.Length > 0)
                    {
                        DescriptionAttribute description = (DescriptionAttribute)attributes[0];
                        return new EnumItem()
                        {
                            Value = value,
                            Description = description.Description,
                            Name = fi.Name
                        };
                    }
                    else
                    {
                        return new EnumItem()
                        {
                            Value = value,
                            Description = value.ToString(),
                            Name = fi.Name
                        };
                    }
                }
            }

            return new EnumItem()
            {
                Value = -1,
                Description = "Enum Değeri Bulunamadı",
            };

        }

        /// <summary>
        /// Enum ismi parametre geçilerek EnumItem olarak geri döndürür.
        /// 
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="name"></param>
        /// <returns></returns>
        public static EnumItem GetItem<T>(string name) where T : struct, IConvertible
        {
            if (!typeof(T).IsEnum)
            {
                throw new ArgumentException("Enum tipi gönderilmeli.");
            }

            Type enumType = typeof(T);
            foreach (T e in Enum.GetValues(enumType))
            {
                FieldInfo fi = enumType.GetField(e.ToString());
                if (fi.Name == name)
                {
                    
                    DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false);
                    if (attributes != null && attributes.Length > 0)
                    {
                        DescriptionAttribute description = (DescriptionAttribute)attributes[0];
                        return new EnumItem()
                        {
                            Value = e.ToInt32(CultureInfo.CurrentCulture.NumberFormat),
                            Description = description.Description,
                            Name = fi.Name
                        };
                    }
                    else
                    {
                        return new EnumItem()
                        {
                            Value = e.ToInt32(CultureInfo.CurrentCulture.NumberFormat),
                            Description = name,
                            Name = fi.Name
                        };
                    }
                }
            }

            return new EnumItem()
            {
                Value = -1,
                Description = "Enum Değeri Bulunamadı",
            };

        }

        /// <summary>
        /// Enum tipine tanımlı tüm değerleri EnumItem listesi olarak döndürür.
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <returns></returns>
        public static List<EnumItem> GetList<T>() where T: struct, IConvertible
        {
            if (!typeof(T).IsEnum)
            {
                throw new ArgumentException("Enum tipi gönderilmeli.");
            }

            List<EnumItem> list = new List<EnumItem>();
            Type enumType = typeof(T);
            foreach (T value in Enum.GetValues(enumType))
            {
                FieldInfo fi = enumType.GetField(value.ToString());
                DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false);
                if (attributes != null && attributes.Length > 0)
                {
                    DescriptionAttribute description = (DescriptionAttribute)attributes[0];
                    list.Add(
                        new EnumItem() { 
                            Value = value.ToInt32(CultureInfo.CurrentCulture.NumberFormat),
                            Description = description.Description,
                            Name = fi.Name
                        });
                }
                else
                {
                    list.Add(
                        new EnumItem() {
                            Value = value.ToInt32(CultureInfo.CurrentCulture.NumberFormat),
                            Description = value.ToString(),
                            Name = fi.Name
                        });
                }
            }

            return list;
        }

    }
}