<?php

header("Content-type:text/html;charset=utf-8");

/**

* 文章编辑类

*/

class Article

{

    protected $content;

    protected $art = null;

    public function __construct($content)

    {

        $this->content = $content;

    }

    public function decorator(){

        return $this->content;

    }

}

/**

* 小编加个摘要

*/

class BianArticle extends Article

{

    public function __construct(Article $art){

        $this->art = $art;

        $this->decorator();

    }

    public function decorator()

    {

        return $this->content = $this->art->content."小编加了个摘要<br>";

    }

}

/**

* SEO对文章描述做了个修改

*/

class SEOArticle extends Article

{

    public function __construct(Article $art){

        $this->art = $art;

        $this->decorator();

    }

    public function decorator()

    {

        return $this->content = $this->art->content."SEO对文章描述做了个修改<br>";

    }

}

$b = new SEOArticle(new BianArticle(new Article("完成了文章编辑<br>")));

echo $b->decorator();