- array_map: documentation ( source)
- implode: documentation ( source)
- key: documentation ( source)
<?php
$input = array (
'Ford Mustang' => '125134',
'Formula 1' => '101499',
'Sconti Auto' => '98331',
);
echo implode(', ', array_map(function ($entry) {
return key($entry);
}, $input));