PHP设计模式之观察者模式定义与用法示例

本文实例讲述了PHP设计模式之观察者模式定义与用法。分享给大家供大家参考，具体如下：

observers = array();
  }
  
  function attach(Observer $observer)
  {
    $this->observers[] = $observer;
  }
  
  function detach(Observer $observer)
  {
    $newObservers = array();
    foreach ($this->observers as $key => $obs) {
      if ($obs !== $observer) {
 $newObservers[] = $obs;
      }
    }
    $this->observers = $newObservers;
  }
  
  function notify()
  {
    foreach ($this->observers as $obs) {
      $obs->update($this);
    }
  }
  
  function handleLogin()
  {
    $ip = rand(1,100);
    switch (rand(1, 3)) {
      case 1:
 $this->setStatus(self::LOGIN_ACCESS, $ip);
 $ret = true;
 break;
      case 2:
 $this->setStatus(self::LOGIN_WRONG_PASS, $ip);
 $ret = false;
 break;
      case 3:
 $this->setStatus(self::LOGIN_USER_UNKNOWN, $ip);
 $ret = false;
 break;
    }
    
    $this->notify();
    return $ret;
  }
  
  function setStatus($status,$ip)
  {
    $this->status = $status;
    $this->ip = $ip;
  }
  
  function getStatus()
  {
    return $this->status;
  }
}

interface Observer {
  function update(Observable $observable);
}

class EmailObserver implements Observer {
  function update (Observable $observable) {
    $status = $observable->getStatus();
    if($status == Login::LOGIN_ACCESS){
//      $this->sendMail('用户ip:'.$observable->ip.'登陆成功!');
      echo __CLASS__.'用户ip:'.$observable->ip.'登陆成功!'.'------------------';
    }
    if($status == Login::LOGIN_WRONG_PASS){
//      $this->sendMail('用户ip:'.$observable->ip.'登陆失败，密码错误!');
      echo __CLASS__.'用户ip:'.$observable->ip.'登陆失败，密码错误!'.'------------------';
    }
    if($status == Login::LOGIN_USER_UNKNOWN){
//      $this->sendMail('用户ip:'.$observable->ip.'登陆失败，无此用户!');
      echo __CLASS__.'用户ip:'.$observable->ip.'登陆失败，无此用户!'.'------------------';
    }
  }
}

class PhoneObserver implements Observer {
  function update (Observable $observable) {
    $status = $observable->getStatus();
    if($status == Login::LOGIN_ACCESS){
//      $this->sendMail('用户ip:'.$observable->ip.'登陆成功!');
      echo __CLASS__.'用户ip:'.$observable->ip.'登陆成功!'.'------------------';
    }
    if($status == Login::LOGIN_WRONG_PASS){
//      $this->sendMail('用户ip:'.$observable->ip.'登陆失败，密码错误!');
      echo __CLASS__.'用户ip:'.$observable->ip.'登陆失败，密码错误!'.'------------------';
    }
    if($status == Login::LOGIN_USER_UNKNOWN){
//      $this->sendMail('用户ip:'.$observable->ip.'登陆失败，无此用户!');
      echo __CLASS__.'用户ip:'.$observable->ip.'登陆失败，无此用户!'.'------------------';
    }
  }
}
class AbcObserver implements Observer {
  function update (Observable $observable) {
    $status = $observable->getStatus();
    if($status == Login::LOGIN_ACCESS){
//      $this->sendMail('用户ip:'.$observable->ip.'登陆成功!');
      echo __CLASS__.'用户ip:'.$observable->ip.'登陆成功!'.'------------------';
    }
    if($status == Login::LOGIN_WRONG_PASS){
//      $this->sendMail('用户ip:'.$observable->ip.'登陆失败，密码错误!');
      echo __CLASS__.'用户ip:'.$observable->ip.'登陆失败，密码错误!'.'------------------';
    }
    if($status == Login::LOGIN_USER_UNKNOWN){
//      $this->sendMail('用户ip:'.$observable->ip.'登陆失败，无此用户!');
      echo __CLASS__.'用户ip:'.$observable->ip.'登陆失败，无此用户!'.'------------------';
    }
  }
}
//实例化登陆信息
$login = new Login();
//实现发邮件观察者
$login->attach(new EmailObserver());
//实现发验证码观察者
$login->attach(new PhoneObserver());
//实现其他观察者
$login->attach(new AbcObserver());
//开始登陆
$login->handleLogin();
?>

运行结果：

EmailObserver用户ip:41登陆失败，无此用户!------------------PhoneObserver用户ip:41登陆失败，无此用户!------------------AbcObserver用户ip:41登陆失败，无此用户!------------------

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