HasFlags always returns true for None (0) value in enum

Question

This is the enum definition:

[Flags]
enum Animals
{
    None = 0,
    Dog = 1,
    Cat = 2,
    Horse = 4,
    Zebra = 8,
}

Now, given the

Answer 1

I ended up removing the 'None' element. It is a 'magic value' and interferes with proper Flags Enum operations (like HasFlag()).

If there is no value then use Nullable i.e. Animals? (which now supports primitive types)

EDIT: I needed a 'Default' value (that is non-zero) for use in a serializable object in order to avoid using Nullable (which conflicted with the business logic). But I think this is still better than using 'None=0'.