reads System.ComponentModel.DescriptionAttributes for each value in an enum, and provides two-way mapping.

EnumDescriptionMapper.cs

static class EnumDescriptionMapper<T>
{
    public static readonly Dictionary<T, string> EnumDescriptions;
    public static readonly Dictionary<string, T> DescriptionsValues;
    
    static EnumDescriptionMapper()
    {
        var values = (T[])Enum.GetValues(typeof(T));
        EnumDescriptions = values.ToDictionary(x => x, GetAttributeDescription);
        DescriptionsValues = EnumDescriptions.ToDictionary(x => x.Value, x => x.Key);
    }

    static string GetAttributeDescription(T t)
    {
        string name = t.ToString();
        var d = typeof(T).GetField(name).GetCustomAttribute<DescriptionAttribute>();
        return d == null ? name : d.Description;
    }
}