• 類名：Observer

• 說明：觀察者模式
  */
  class Observer{
  // 聲明存放觀察者容器
  protected $container = array();

  /*

  • 新增觀察者函數
    */
    public function addObserver($type, $observer) {
    $this->container[$type][] = $observer;
    }

  /*

  • 運行訂單觀察者
    */
    public function runObserver($type,$obj) {
    if (isset($this->container[$type])) {
    
    foreach ($this->container[$type] as $obser) {
    $obj = new $obser();
    $obj->update($obj);
    }
    }
    }
    }

/**

• 類名：Order
• 說明：訂單類

• 觀察者模式的使用
  */
  class Order {

  /*

  • 創建訂單
    */
    public function create($type,$observer) {
    echo ‘購買成功<br/>‘;
    $observer->runObserver($type,$this);
    }
    }

/*

• 類名：Email
• 說明：郵件類
  */
  class Email {
  public static function update($order) {
  
  echo ‘發送郵件<br/>‘;
  }
  }
  class Status {
  public static function update($order) {
  echo ‘改變訂單狀態<br/>‘;
  }
  }

$type1 = ‘buy‘;
$observer = new Observer();
$observer->addObServer($type1, ‘Email‘);
$observer->addObServer($type1, ‘Status‘);

$order = new Order();
$order->create($type1,$observer);

class Supply{

class Sms{
public static function update($supply){
echo "推送消息";
}
}

$type2 = ‘release‘;
$observer2 = new Observer();
$observer2->addObserver($type2,‘Sms‘);

$supply = new Supply();
$supply->release($type2,$observer2);

觀察者模式小示例