__serialize() method

The __serialize() magic method is called when a script tries to construct an associative array of key/value pairs that represent the serialized form of the object.

If no array is returned a TypeError will be thrown.

<?php
     class WebPage {
             private $html;
             private $url;

         public function __construct($url) {
             $this->url = $url;
         }

             public function __serialize() {
                     return array('url' => $url);
             }

             public function __unserialize($arg) {
                     $this->url = $arg['url'];
                     $this->html = file_get_contents($this->url);
             }

     }
?>

Documentation

See also Serializing Data In PHP

Related : Unserialization, __unserialize() method, Serialization, Serialization, Unserialization