php克隆的实现方法介绍（代码示例）

<?php

class A{
    public $value = 1;
}

class B{
    public $value = 1;
    public $a = null;

    public function __Construct(){
        $this->a = new A();
    }
}

$b = new B();
$d = 1;
$e = $d;
$e++;
echo "写时复制\n";
echo $d."\n";
echo $e."\n";

echo "------------------------------------\n";

$c = $b;
$c->a->value++;
$c->value++;

echo "对象中的对象变量\n";
echo $b->a->value."\n";
echo $c->a->value."\n";

echo "对象变量中的值变量\n";
echo $b->value."\n";
echo $c->value."\n";

echo "--------------------------------------\n";
$f = clone $b;
$f->value++;
$f->a->value++;

echo "对象变量中的值变量\n";
echo $b->value."\n";
echo $f->value."\n";

echo "对象中的对象变量\n";
echo $b->a->value."\n";
echo $f->a->value."\n";


?>