مشکل در تابع set__ (حل شد)

<?php class test { private $number = ""; public function __construct() { $this->number = 500; } public function __get($name) { return $this->{$name}; } public function __set($name, $value) { switch ($name) { case '10': $this->number = $value; break; case '20': echo 'number 20 is bigger!'; break; default : echo 'Success'; break; } return $name; } public function show() { echo '<p>' . $this->number . '</p>'; } } $p = new test(); //$p->show(); echo $p->number; $p->number = 10; echo $p->number; ?>