原型模式

<?php
class color {
    public $name = ‘红色‘;
}

class prototype {
    private $color = null;
    public function __construct (color $color) {
        $this->color = $color;
    }
    public function clone_self() {
        $obj = clone $this;
        $obj->color = clone $obj->color; //深复制 复制对象已持有的对象
        return $obj;
        //return clone $this; //浅复制 不会复制对象持有的对象
    }
    public function get_color() {
        echo $this->color->name,chr(10);
    }
}
$color = new color();
$a = new prototype($color);
$a->get_color(); //红色
$b = $a->clone_self();
$color->name = ‘绿色‘;
$a->get_color(); //绿色
$b->get_color(); //红色