Deleting an array element within foreach loop

Question

I have a simple array which contains name of all the countries and total number of users registered on my website from that each country. It's something like this:

Array (
    [1] => Array ( [name] => Afghanistan [total] => 3 )
    [2] => Array ( [name] => Albania [total] => 0 )
)

And, I'm trying to delete array elements (countries) which have 0 users.

I've tried with this code and it's not working:

foreach($country as $row) {
    if ($row['total'] == 0) {
        unset($row);
    }
}

What is wrong with this code?

Answer 1

If you unset($row) you are only removing the local variable.

Instead fetch the key and remove that:

foreach ($country as $i => $row) {
    if ($row['total'] == 0) {
        unset($country[$i]);
    }
}

Answer 2

Foreach creates copies of the keys/values on the array you're looping over, so all you're doing is unsetting the local copy, not the original that's actually in the array. Either access the array directly

foreach($country as $key => $row) {
  if ($row['total'] == 0) {
     unset($country[$key]);
  }
}

or use a reference, unset it and filter NULL elements afterwards:

foreach($country as &$row) {
    if ($row['total'] == 0) {
        $row = (unset) $row;
    }
}
unset($row);
$country = array_filter($country);