Metoda __clone

Metoda __clone se samodejno pokliče ob uporabi operatorja clone. Omogoča določitev lastne logike kopiranja objekta. Privzeto PHP izvede plitvo kopiranje vseh lastnosti objekta. Metoda __clone je uporabna, ko je treba implementirati globoko kopiranje ali spremeniti obnašanje pri kloniranju.

Sintaksa

public function __clone(): void

Primer

Implementirajmo osnovno kloniranje objekta:

<?php
	class User {
		public $name;
		
		public function __construct($name) {
			$this->name = $name;
		}
		
		public function __clone() {
			echo 'Objekt je bil kloniran';
		}
	}
	
	$user1 = new User('John');
	$user2 = clone $user1;
?>

Rezultat izvajanja kode:

'Objekt je bil kloniran'

Primer

Implementirajmo globoko kopiranje objekta z vgnezdjenimi objekti:

<?php
	class Address {
		public $city;
		
		public function __construct($city) {
			$this->city = $city;
		}
	}
	
	class User {
		public $name;
		public $address;
		
		public function __construct($name, $city) {
			$this->name = $name;
			$this->address = new Address($city);
		}
		
		public function __clone() {
			$this->address = clone $this->address;
		}
	}
	
	$user1 = new User('John', 'New York');
	$user2 = clone $user1;
	$user2->address->city = 'Boston';
	
	echo $user1->address->city;
?>

Rezultat izvajanja kode:

'New York'

Primer

Dodajmo unikatni identifikator pri kloniranju:

<?php
	class Product {
		public $id;
		public $name;
		
		public function __construct($name) {
			$this->id = uniqid();
			$this->name = $name;
		}
		
		public function __clone() {
			$this->id = uniqid();
		}
	}
	
	$product1 = new Product('Laptop');
	$product2 = clone $product1;
	
	echo $product1->id . ' ' . $product2->id;
?>

Rezultat izvajanja kode (primer):

'5f1a2b3c 5f1a2b3d'

Glejte tudi

metodo __construct,
ki je konstruktor objekta