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Michael Caley
Michael Caley
5,376 Points

Why would we use array_walk instead of foreach?

Please can you give me an example of when to use each one and the difference.

1 Answer

Samy Basset
Samy Basset
11,862 Points

Hey Micheal,

With a foreach loop we can loop trough an array(inside the loop) e.g. :

$arr = [1, 2, 3, 4];

foreach($arr as $num) {
  echo $num . '<br>';

and with the array_walk function you can loop trough the array with a function like this:

$arr = ['1', 2, 3, 4];

function foo($value, $key) {
  echo 'This is the ' . $key . ' and this is the ' . $value . '<br>';

array_walk($arr, 'foo');

As you can see, the first parameter for the array_walk function is the name of the array. The second parameter is the name of the function in quotes.

I hope this helps you.