PHP Sort Array based on values ​​in another

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PHP - sort an array based on another array?

Need some help regarding array sorting....

I have two arrays. The main one (where the key is the user id) :

$user[31] = 'Tom'

$user[43] = 'Jane'

and another array with the order they should be displayed (where key is the order and value is the user id) :

$order[1] = 43

$order[2] = 31

How can I apply the ordering to the main array using the ordering one?

Thanks guys!

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Use the keys in $order to select the users from $user in the right order:

$orderedUsers = array();
foreach ($order as $key) {
    $orderedUsers[] = $user[$key];
}