php装饰器

<?php
 
/*
 * 用一个类来装饰另一个类,动态的给一个对象增加一些额外功能,这些功能一般是在这个对象调用方法前或方法后
 * 比如我们要给User类增加一个登陆日志的功能
 */
 
// 抽象构件
abstract class Component
{
    abstract public function login($time);
}
 
// user类
class User extends Component
{
    private $login_time;
 
    public function login($time)
    {
        $this->login_time = $time;
    }
 
}
 
// 装饰器
class LogDecorate extends Component
{
    private $user;
    private $time;
    /**
     * Log constructor.
     */
    public function __construct(User $user)
    {
        $this->user = $user;
    }
 
    public function login($time)
    {
        $this->user->login($time);
        $this->log($time);
    }
 
    public function log($time)
    {
        echo sprintf("Log: login %d",$time) . PHP_EOL;
    }
 
}
 
$user = new User();
$log = new LogDecorate($user);
$log->login(time());