php man page for serializable

SERIALIZABLE(3) 							 1							   SERIALIZABLE(3)

The Serializable interface

INTRODUCTION
	Interface for customized serializing.

	Classes  that  implement  this	interface  no longer support __sleep() and __wakeup(). The method serialize is called whenever an instance
       needs to be serialized. This does not invoke __destruct() or has any other side effect unless programmed inside the method. When  the  data
       is unserialized the class is known and the appropriate unserialize() method is called as a constructor instead of calling __construct(). If
       you need to execute the standard constructor you may do so in the method.

INTERFACE SYNOPSIS
       Serializable

       Serializable

       Methods

       o abstractpublic string Serializable::serialize (void  )

       o abstractpublic void Serializable::unserialize (string	$serialized)

       Example #1

	      Basic usage

	      <?php
	      class obj implements Serializable {
		  private $data;
		  public function __construct() {
		      $this->data = "My private data";
		  }
		  public function serialize() {
		      return serialize($this->data);
		  }
		  public function unserialize($data) {
		      $this->data = unserialize($data);
		  }
		  public function getData() {
		      return $this->data;
		  }
	      }

	      $obj = new obj;
	      $ser = serialize($obj);

	      var_dump($ser);

	      $newobj = unserialize($ser);

	      var_dump($newobj->getData());
	      ?>

	      The above example will output something similar to:

	      string(38) "C:3:"obj":23:{s:15:"My private data";}"
	      string(15) "My private data"

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