Neatest way to 'OR' all values in a Flagged Enum?

Question

Given the enum:

[Flags]
public enum mytest
{
    a = 1,
    b = 2,
    c = 4
}

I\'ve come up with two ways to represent all va

Answer 1

For a generic method, use Linq's Enumerable.Aggregate extension method;

var flags = Enum.GetValues(typeof(mytest))
                .Cast()
                .Aggregate(0, (s, f) => s | f);

Or in a wrapper method

TEnum GetAll() where TEnum : struct
{
    return (TEnum) (object)
            Enum.GetValues(typeof(TEnum))
                .Cast()
                .Aggregate(0, (s, f) => s | f);
}

full credit for this double-cast trick goes to @millimoose