How does the usort function in PHP compare to custom array sorting methods?

The usort function in PHP allows for custom sorting of an array based on a user-defined comparison function. This function can be used to sort arrays in ways that the built-in sorting functions cannot achieve. By providing a custom comparison function, usort gives developers more flexibility and control over the sorting process.

// Example of using usort to sort an array of numbers in descending order
$numbers = [5, 2, 8, 1, 9];

usort($numbers, function($a, $b) {
    if ($a == $b) {
        return 0;
    }
    return ($a > $b) ? -1 : 1;
});

print_r($numbers);