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<?php function json_is($string) { try { // try to decode string json_decode($string); } catch (ErrorException $e) { // exception has been caught which means argument wasn't a string and thus is definitely no json. return FALSE; } // check if error occured return (json_last_error() == JSON_ERROR_NONE); } /** * Checks whether a string is valid json. * * @param string $string * @return boolean */ function isJson($string, $assoc = false) { // Make sure the string is not empty and is, in fact, a string. // An empty string is not valid JSON. if(!empty($string) && is_string($string)) { json_decode($string, $assoc); return (json_last_error() == JSON_ERROR_NONE); // return json_decode($str) != null; } return false; } $a=['arraiii'=>['dentro'=>234]]; $b=json_encode($a); $c=''; echo json_decode(''); var_dump(isJson($c));

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