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

phppublic function __clone(): void

Primer

Implementirajmo osnovno kloniranje objekta:

php<?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:

php'Objekt je bil kloniran'

Primer

Implementirajmo globoko kopiranje objekta z vgnezdjenimi objekti:

php<?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:

php'New York'

Primer

Dodajmo unikatni identifikator pri kloniranju:

php<?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):

php'5f1a2b3c 5f1a2b3d'

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