Spotify.NET/SpotifyAPI.Web/Util/StringAttribute.cs

using System;
using System.Reflection;
using System.Linq;
using System.Diagnostics.CodeAnalysis;

namespace SpotifyAPI.Web
{
  [AttributeUsage(AttributeTargets.Field)]
  public class StringAttribute : Attribute
  {
    public StringAttribute(string value)
    {
      Value = value;
    }

    public string Value { get; set; }

#if NETSTANDARD2_1
    public static bool GetValue(Type enumType, Enum enumValue, [NotNullWhen(true)] out string? result)
#endif
#if NETSTANDARD2_0
    public static bool GetValue(Type enumType, Enum enumValue, out string? result)
#endif
    {
      Ensure.ArgumentNotNull(enumType, nameof(enumType));
      Ensure.ArgumentNotNull(enumValue, nameof(enumValue));

      if (enumType
        .GetMember(enumValue.ToString())[0]
        .GetCustomAttributes(typeof(StringAttribute))
        .FirstOrDefault() is StringAttribute stringAttr)
      {
        result = stringAttr.Value;
        return true;
      }
      result = null;
      return false;
    }
  }
}