What are the differences between using unlink() and a loop to delete elements from an array in PHP, and which method is more efficient?

When deleting elements from an array in PHP, using a loop to iterate over the array and unset the elements is a common approach. However, this can be inefficient for large arrays as it requires iterating over each element. Another method is to use the unlink() function, which directly removes elements from the array without the need for a loop. This method can be more efficient for large arrays.

// Using a loop to delete elements from an array
$array = [1, 2, 3, 4, 5];
foreach ($array as $key => $value) {
    if ($value == 2) {
        unset($array[$key]);
    }
}

// Using unlink() to delete elements from an array
$array = [1, 2, 3, 4, 5];
$key = array_search(2, $array);
if ($key !== false) {
    unset($array[$key]);
}