Question

I was wondering what’s the difference the two cases below, and which one is recommended?

$val = 0;

if (!$val) {
  //True
}

if (empty($val) {
  //It's also True
}

Answer 1

Have a look at the PHP type comparison table.

If you check the table, you’ll notice that for all cases, empty($x) is the same as !$x. So it comes down to handling uninitialised variables. !$x creates an E_NOTICE, whereas empty($x) does not.