Kaedah __clone

Kaedah __clone dipanggil secara automatik apabila menggunakan operator clone. Ia membolehkan anda menentukan logik penyalinan objek sendiri. Secara lalai, PHP melakukan penyalinan cetusan semua sifat objek. Kaedah __clone berguna apabila perlu melaksanakan penyalinan mendalam atau mengubah tingkah laku semasa pengklonan.

Sintaks

phppublic function __clone(): void

Contoh

Laksanakan pengklonan objek asas:

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

Keputusan pelaksanaan kod:

php'Objek diklon'

Contoh

Laksanakan penyalinan mendalam objek dengan objek bersarang:

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;
?>

Keputusan pelaksanaan kod:

php'New York'

Contoh

Tambahkan pengecam unik semasa pengklonan:

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;
?>

Keputusan pelaksanaan kod (contoh):

php'5f1a2b3c 5f1a2b3d'

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