csharp .net片段

Posted 2021-05-12

using System.ComponentModel;
using System.Linq;
using System.Reflection;

namespace System
{
    public static class EnumExtensions
    {
        /// <summary>
        /// Enum에 선언된 <see cref="DescriptionAttribute" />의 값을 반환한다.
        /// </summary>
        /// <remarks>
        /// cf. https://stackoverflow.com/a/479417/3781540
        /// </remarks>
        public static string GetDescription<T>(this T enumerationValue) where T : struct
        {
            Type type = enumerationValue.GetType();
            if (!type.GetTypeInfo().IsEnum)
            {
                throw new ArgumentException("EnumerationValue must be of Enum type", "enumerationValue");
            }

            //Tries to find a DescriptionAttribute for a potential friendly name
            //for the enum
            MemberInfo[] memberInfo = type.GetMember(enumerationValue.ToString());
            if (memberInfo != null && memberInfo.Length > 0)
            {
                var attrs = memberInfo[0].GetCustomAttributes(typeof(DescriptionAttribute), false).ToArray();
                if (attrs != null && attrs.Length > 0)
                {
                    //Pull out the description value
                    return ((DescriptionAttribute)attrs[0]).Description;
                }
            }

            //If we have no description attribute, just return the ToString of the enum
            return enumerationValue.ToString();
        }
    }
}