php對象克隆

<?php
/**
 * Created by PhpStorm.
 * User: tusi
 * Date: 2017/8/25
 * Time: 10:21
 */
class SubObject
{
    static $instances=0;
    public $instance;

    public function __construct(){
        $this->instance=++self::$instances;
    }//構造函數，每實例化對象一次，將公有屬性$instance值加1

    public function __clone(){
        $this->instance=++self::$instances;
    }//對象複製函數，如果對象中定義了__clone方法，則複製生成的對象中的__clone方法會被調用
}

class MyCloneable
{
    public $object1;
    public $object2;

    function __clone(){
        //強制複製一份this->object1,否則仍然指向同一個對象。
        $this->object1=clone $this->object1;
    }
}

$obj=new MyCloneable();

$obj->object1=new SubObject();
$obj->object2=new SubObject();

$obj2=clone $obj;

echo '<pre>';
echo "Original Object:"."<br />";
var_dump($obj);
echo "Cloned Object:"."<br />";
var_dump(($obj2));

運行如下：