Question

Normally when comparing flag enums I use the following format:

(value & flag) == flag;

But sometimes I come across this:

(value & flag) != 0;

Just wondering which is the better to use, or does it come down to personal preference?

Answer 1

So long as flag is a one-bit flag, they are equivalent. If flag has multiple bits,

(value & flag) == flag;

is a logical AND (ALL bits must match) while

(value & flag) != 0;

is a logical OR (ANY of the bits must match).