- var_dump: documentation ( source)
- bin2hex: documentation ( source)
- print_r: documentation ( source)
<?php
$arr = [
"-1" => "item 1",
"1" => "item 2",
"\0-1" => "item 3",
];
print_r($arr);
var_dump($arr);
foreach ($arr as $k => $v) {
print bin2hex($k) ."\n";
}