Get a List of my enum attributes with a generic method

Question

At start, we have this basic enum.

public enum E_Levels {

    [ValueOfEnum(\"Low level\")]
    LOW,

    [ValueOfEnum(\"Normal level\")]
    NORMAL,

    [V         


        

Answer 1

Let's try to keep this more general purpose.

I have an extension method that could grab attributes off of enum values. This would give you quick access to the attributes.

public static class EnumExtensions
{
    public static TAttribute GetAttribute(this Enum value)
        where TAttribute : Attribute
    {
        var type = value.GetType();
        var name = Enum.GetName(type, value);
        return type.GetField(name)
            .GetCustomAttributes(false)
            .OfType()
            .SingleOrDefault();
    }
}

Using this, you could create some queries to get what you want.

var valuesOfLevels =
    Enum.GetValues(typeof(E_Levels)).Cast()
        .Select(level => level.GetAttribute().Value);

So your GetValuesOf() method (which is not a great name for such a specialty method IMHO) can be written like this:

public static List GetValuesOf()
    where TEnum : struct // can't constrain to enums so closest thing
{
    return Enum.GetValues(typeof(TEnum)).Cast()
               .Select(val => val.GetAttribute().Value)
               .ToList();
}

Now you may call the method like so:

var levelValues = GetValueOf();
// levelValues = { "Low level", "Normal level", "High level" }