README.md

EnumDesc

A library that automatically adds support for getting description of enum in c#.

When you have an enum and it has at least one member marked with the Description attribute, EnumDesc will automatically generate an extension method named GetDescription for it.

And then EnumDesc will generate an Enum<T> class that provides GetDescriptionList and GetDescriptionDic methods.

Get Started

EnumDesc can be installed using the Nuget package manager or the dotnet CLI.

dotnet add package EnumDesc

Example

For example, there is a enum named Colour:

public enum Colour
{
    [Description("Color Blue")]
    Blue,

    [Description("Color Red")]
    Red
}

The EnumDesc will generate a file named EnumDesc.g.cs:

namespace YourNamespace
{
    public static partial class ColourExtensions
    {
        public static string GetDescription(this Colour colour)
        {
            return colour switch
            {
                Colour.Blue => "Color Blue",
                Colour.Red => "Color Red",
                _ => string.Empty
            };
        }
    }

    public partial class Enum<TEnum> where TEnum : Enum
    {
        public static IEnumerable<(TEnum? value, string desc)> GetDescriptionList() => GetDescriptionList<TEnum>();

        public static IEnumerable<(TValue? value, string desc)> GetDescriptionList<TValue>(bool withAll = false, string allDesc = "All", TValue? allValue = default)
        {
            var enumType = typeof(TEnum);

            int index = 0;

            (TValue? value, string desc)[] result;

            if (enumType.Equals(typeof(Colour)))
            {
                if (withAll)
                {
                    result = new (TValue? value, string desc)[3];
                    result[index++] = (allValue, allDesc);
                }
                else
                {
                    result = new (TValue? value, string desc)[2];
                }

                result[index++] = ((TValue)(object)Colour.Blue, "Color Blue");
                result[index++] = ((TValue)(object)Colour.Red, "Color Red");
            }
            else
            {
                throw new NotSupportedException($"No member in {enumType.FullName} has Description attribute.");
            }

            return result;
        }

        public static Dictionary<TEnum, string> GetDescriptionDic() => GetDescriptionDic<TEnum>();

        public static Dictionary<TValue, string> GetDescriptionDic<TValue>(bool withAll = false, string allDesc = "All", TValue allValue = default!) where TValue : notnull
        {
            var enumType = typeof(TEnum);

            var result = new Dictionary<TValue, string>();

            if (withAll)
            {
                result.Add(allValue, allDesc);
            }

            if (enumType.Equals(typeof(Colour)))
            {
                result.Add((TValue)(object)Colour.Blue, "Color Blue");
                result.Add((TValue)(object)Colour.Red, "Color Red");
            }
            else
            {
                throw new NotSupportedException($"No member in {enumType.FullName} has Description attribute.");
            }

            return result;
        }
    }
}

Usage:

var blueDesc = Colour.Blue.GetDescription();
// "Color Blue"

IEnumerable<(Colour color, string desc)> descList = Enum<Colour>.GetDescriptionList();
// [(Colour.Blue, "Color Blue"), (Colour.Red, "Color Red")]

Dictionary<Colour, string> descDic = Enum<Colour>.GetDescriptionDic();
// {Colour.Blue: "Color Blue"， Colour.Red: "Color Red"}

Benchmarks

GetDescription()

BenchmarkDotNet=v0.13.1, OS=Windows 10.0.22000
AMD Ryzen 7 5800H with Radeon Graphics, 1 CPU, 16 logical and 8 physical cores
.NET SDK=6.0.200
  [Host]     : .NET 6.0.2 (6.0.222.6406), X64 RyuJIT
  DefaultJob : .NET 6.0.2 (6.0.222.6406), X64 RyuJIT

Method	Mean	Error	StdDev	Median
EnumReflection	849.1797 ns	11.9885 ns	11.2141 ns	847.9369 ns
EnumDesc	0.0311 ns	0.0399 ns	0.0354 ns	0.0217 ns

Enum<T>.GetDescriptionList()

BenchmarkDotNet=v0.13.1, OS=Windows 10.0.22000
AMD Ryzen 7 5800H with Radeon Graphics, 1 CPU, 16 logical and 8 physical cores
.NET SDK=6.0.200
  [Host]     : .NET 6.0.2 (6.0.222.6406), X64 RyuJIT
  DefaultJob : .NET 6.0.2 (6.0.222.6406), X64 RyuJIT

Method	Mean	Error	StdDev
EnumReflection	2,169.89 ns	29.367 ns	27.470 ns
EnumDesc	42.74 ns	0.679 ns	0.635 ns

Enum<T>.GetDescriptionDic()

BenchmarkDotNet=v0.13.1, OS=Windows 10.0.22000
AMD Ryzen 7 5800H with Radeon Graphics, 1 CPU, 16 logical and 8 physical cores
.NET SDK=6.0.200
  [Host]     : .NET 6.0.2 (6.0.222.6406), X64 RyuJIT
  DefaultJob : .NET 6.0.2 (6.0.222.6406), X64 RyuJIT

Method	Mean	Error	StdDev
EnumReflection	2,487.17 ns	19.692 ns	18.420 ns
EnumDesc	32.67 ns	0.442 ns	0.413 ns