参考：https://www.cnblogs.com/onephp/p/6108940.html

●装饰器模式（Decorator），可以动态地添加修改类的功能

●一个类提供了一项功能，如果要在修改并添加额外的功能，传统的编程模式，需要写一个子类继承它，并重新实现类的方法

●使用装饰器模式，仅需在运行时添加一个装饰器对象即可实现，可以实现最大的灵活性

<?php/** * 输出一个字符串 * 装饰器动态添加功能 * Class EchoText */class EchoText{ protected $decorator = []; public function Index() { //调用装饰器前置操作 $this->beforeEcho(); echo "你好，我是装饰器。"; //调用装饰器后置操作 $this->afterEcho(); } //增加装饰器 public function addDecorator(Decorator $decorator) { $this->decorator[] = $decorator; } //执行装饰器前置操作 先进先出原则 protected function beforeEcho() { foreach ($this->decorator as $decorator) $decorator->before(); } //执行装饰器后置操作 先进后出原则 protected function afterEcho() { $tmp = array_reverse($this->decorator); foreach ($tmp as $decorator) $decorator->after(); }}/** * 装饰器接口 * Class Decorator */interface Decorator{ public function before(); public function after();}/** * 颜色装饰器实现 * Class ColorDecorator */class ColorDecorator implements Decorator{ protected $color; public function __construct($color) { $this->color = $color; } public function before() { echo "<dis style=‘color: {$this->color}‘>"; } public function after() { echo "</div>"; }}/** * 字体大小装饰器实现 * Class SizeDecorator */class SizeDecorator implements Decorator{ protected $size; public function __construct($size) { $this->size = $size; } public function before() { echo "<dis style=‘font-size: {$this->size}px‘>"; } public function after() { echo "</div>"; }}//实例化输出类$echo = new EchoText();//增加装饰器$echo->addDecorator(new ColorDecorator(‘red‘));//增加装饰器$echo->addDecorator(new SizeDecorator(‘22‘));//输出$echo->Index();

php-decorator