The PHP array_walk() function runs each array element in a user-defined function with the array’s keys and values as parameters in the function.

<?php
function my_function($value, $key, $param) {
    echo $key . $param . $value;
    echo '<br>';
}

$a = array('Car 1' => 'Lamborghini', 'Car 2' => 'Ferrari', 'Car 3' => 'Maserati');
array_walk($a, 'my_function', '- has the value ');
?>

Car 1 - has the value Lamborghini
Car 2 - has the value Ferrari
Car 3 - has the value Maserati

array_walk(array, my_function, parameter, ...)