Serializing child and parent classes:
<?php
class MyClass implements Serializable {
private $data;
public function __construct($data) {
$this->data = $data;
}
public function getData() {
return $this->data;
}
public function serialize() {
echo "Serializing MyClass...\n";
return serialize($this->data);
}
public function unserialize($data) {
echo "Unserializing MyClass...\n";
$this->data = unserialize($data);
}
}
class MyChildClass extends MyClass {
private $id;
private $name;
public function __construct($id, $name, $data) {
parent::__construct($data);
$this->id = $id;
$this->name = $name;
}
public function serialize() {
echo "Serializing MyChildClass...\n";
return serialize(
array(
'id' => $this->id,
'name' => $this->name,
'parentData' => parent::serialize()
)
);
}
public function unserialize($data) {
echo "Unserializing MyChildClass...\n";
$data = unserialize($data);
$this->id = $data['id'];
$this->name = $data['name'];
parent::unserialize($data['parentData']);
}
public function getId() {
return $this->id;
}
public function getName() {
return $this->name;
}
}
$obj = new MyChildClass(15, 'My class name', 'My data');
$serial = serialize($obj);
$newObject = unserialize($serial);
echo $newObject->getId() . PHP_EOL;
echo $newObject->getName() . PHP_EOL;
echo $newObject->getData() . PHP_EOL;
?>
This will output:
Serializing MyChildClass...
Serializing MyClass...
Unserializing MyChildClass...
Unserializing MyClass...
15
My class name
My data
The Serializable interface
(PHP 5 >= 5.1.0)
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
{
/* Methods */
}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"
Table of Contents
- Serializable::serialize — String representation of object
- Serializable::unserialize — Constructs the object
add a note
User Contributed Notes 5 notes
marcos dot gottardi at folha dot REM0VE-THIS dot com dot br ¶
3 years ago
grzeniufication ¶
1 month ago
Here's an example how to un-, serialize more than one property:
class Example implements \Serializable
{
protected $property1;
protected $property2;
protected $property3;
public function __construct($property1, $property2, $property3)
{
$this->property1 = $property1;
$this->property2 = $property2;
$this->property3 = $property3;
}
public function serialize()
{
return serialize([
$this->property1,
$this->property2,
$this->property3,
]);
}
public function unserialize($data)
{
list(
$this->property1,
$this->property2,
$this->property3
) = unserialize($data);
}
}
grzeniufication ¶
1 month ago
Here's an example how to un-, serialize more than one property:
class Example implements \Serializable
{
protected $property1;
protected $property2;
protected $property3;
public function __construct($property1, $property2, $property3)
{
$this->property1 = $property1;
$this->property2 = $property2;
$this->property3 = $property3;
}
public function serialize()
{
return serialize([
$this->property1,
$this->property2,
$this->property3,
]);
}
public function unserialize($data)
{
list(
$this->property1,
$this->property2,
$this->property3
) = unserialize($data);
}
}
Olivier Pons ¶
1 year ago
Here's the way you could implement serializable so that *ALL* descendant serialize themselves without the need of re-writing for all descendant the functions serialize() and unserialize().
Note : this will only serialize "visible" properties, this it won't serialize private descendant properties. If you dont want a property of a descendant to be serialized, make it private.
class Pot implements Serializable
{
protected $_a;
protected $_b;
public function serialize()
{
return serialize(get_object_vars($this));
}
public function unserialize($data)
{
$values = unserialize($data);
foreach ($values as $key=>$value) {
$this->$key = $value;
}
}
}
And now one descendant:
class PotId implements Pot
{
protected $_k;
}
class Pots implements PotId
{
protected $_l;
}
$pots = new Pots();
and calling serialize($pots) will serialize all properties ($_a, $_b, $_k, $l).
Anonymous ¶
4 years ago
You can prevent an object getting unserialized by returning NULL. Instead of a serialized object, PHP will return the serialized form of NULL:
<?php
class testNull implements Serializable {
public function serialize() {
return NULL;
}
public function unserialize($data) {
}
}
$obj = new testNull;
$string = serialize($obj);
echo $string; // "N;"
?>
That's perhaps better than throwing exceptions inside of the serialize function if you want to prevent serialization of certain objects.
