- array_map: documentation ( source)
- var_dump: documentation ( source)
- str_replace: documentation ( source)
- strtolower: documentation ( source)
<?php
$test = [
'Hello 123',
'walala7',
'HoHo HoHo',
'FOO bar'
];
var_dump(array_map(function($item) { return str_replace(' ', '_', strtolower($item)); } , $test));