php数据如何使用观察者模式解耦_php数据观察者模式事件处理

interface Observer {
    public function update($event, $data);
}

interface Subject {
    public function attach(Observer $observer);
    public function detach(Observer $observer);
    public function notify($event, $data);
}

class User implements Subject {
    private $observers = [];
    private $name;

    public function __construct($name) {
        $this->name = $name;
    }

    public function attach(Observer $observer) {
        $this->observers[] = $observer;
    }

    public function detach(Observer $observer) {
        $this->observers = array_filter(
            $this->observers,
            fn($o) => $o !== $observer
        );
    }

    public function register() {
        // 模拟注册逻辑
        echo "用户 {$this->name} 注册成功\n";
        // 触发事件
        $this->notify('user.registered', ['name' => $this->name]);
    }

    public function notify($event, $data) {
        foreach ($this->observers as $observer) {
            $observer->update($event, $data);
        }
    }
}

class EmailService implements Observer {
    public function update($event, $data) {
        if ($event === 'user.registered') {
            echo "发送欢迎邮件给 {$data['name']}\n";
        }
    }
}

class LogService implements Observer {
    public function update($event, $data) {
        echo "日志记录：用户 {$data['name']} 已注册\n";
    }
}

$user = new User("张三");
$user->attach(new EmailService());
$user->attach(new LogService());
$user->register();