Extension method on enumeration, not instance of enumeration

Question

I have an enumeration for my Things like so:

public enum Things
{
   OneThing,
   AnotherThing
}

I would like to write an extension method

Answer 1

I use 'Type' instead of 'Enum' to add extension. Then I can get any type of list back from the method. Here it returns string values:

    public static string[] AllDescription(this Type enumType)
    {
        if (!enumType.IsEnum) return null;

        var list = new List();
        var values = Enum.GetValues(enumType);

        foreach (var item in values)
        {
            // add any combination of information to list here:
            list.Add(string.Format("{0}", item));

            //this one gets the values from the [Description] Attribute that I usually use to fill drop downs
            //list.Add(((Enum) item).GetDescription());
        }

        return list.ToArray();
    }

Later I could use this syntax to get what I want:

var listOfThings = typeof (Things).AllDescription();