1 <?php 2  3 /** 4  * 和装饰器模式的区别：装饰器模式为了增强功能，而代理模式是为了加以控制 5  * 6  * 装饰器为对象添加一个或多个功能，而代理则控制对对象的访问 7  */ 8  9 interface image10 {11     public function display();12 }13 14 class RealImage implements image15 {16     private $_imgSrc;17 18     public function __construct($imgSrc)19     {20         $this->_imgSrc = http://www.mamicode.com/$imgSrc;21         $this->loadFromDisk();22     }23 24     private function loadFromDisk()25     {26         echo "Load {$this->_imgSrc} from disk<br/>";27     }28 29     public function display()30     {31         echo "Display {$this->_imgSrc}";32     }33 }34 35 36 class ProxyImage implements image37 {38     private $_imgSrc;39     private $_realImage;40 41     public function __construct($imgSrc)42     {43         $this->_imgSrc = http://www.mamicode.com/$imgSrc;44     }45 46     public function display()47     {48         if (!$this->_realImage instanceof RealImage) {49             $this->_realImage = new RealImage($this->_imgSrc);50         }51 52         $this->_realImage->display();53     }54 }55 56 57 58 $p = new ProxyImage(‘a.png‘);59 $p->display();60 61 echo "<br/><br/>";62 $p->display();