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

This is just the defined behavior of the HasFlag method. From the MSDN documentation

if the underlying value of flag is zero, the method returns true