Question

I’m working with a large array. We’re displaying all fields of data in the array with a table. Some fields in the array are null because the user hasn’t accumulated anything in that field. However, we wanted a zero for when they have such a result. Our solution was to display the value along with intval()

intval(@$users[$user_id]['loggedin_time'])

Which is fine, but it is ugly and inelegant. Is there a way, without a foreach loop, to set all values of ” in the array to be 0?

Answer 1

Yes, with array_map:

$input = array(...);
$output = array_map(function($item) { return $item ?: 0; }, $input);

The above example uses facilities of PHP >= 5.3 (inline anonymous function declaration and the short form of the ternary operator), but you can do the same in any PHP version (only perhaps more verbosely).

You should think a bit about the conditional inside the callback function; the one I ‘m using here will replace all values that evaluate to false as booleans with zeroes (this does include the empty string, but it also includes e.g. null values — so you might want to tweak the condition, depending on your needs).

Update: PHP < 5.3 version

It’s either this:

function callback($item) {
    return $item == false ? 0 : $item;
}

$output = array_map('callback', $input);

Or this:

$output = array_map(
     create_function('$item', 'return $item == false ? 0 : $item;'),
     $input);