3v4l.org

run code in 300+ PHP versions simultaneously
<?php function isJson($string) { if(is_string($string)) { json_decode($string); return (json_last_error() == JSON_ERROR_NONE); } return false; } $a=['arraiii'=>['dentro'=>234]]; $b=json_encode($a); var_dump(isJson($b));

preferences:
38.18 ms | 402 KiB | 5 Q