php设计模式--装饰模式（七）装饰模式完成文章编辑

<?php
//装饰器模式做文章修饰功能
class BaseArt {
  protected $content;
  protected $art = null;
  public function __construct($content) { 
    $this->content = $content ;
  }
  public function decorator() {
    return $this->content;
  }
}
/*  
class BianArt extends BaseArt{
  public function decorator(){
   return parent::decorator()."小编加了摘要";
  }
}
  
class SEOArt extends BaseArt{
  public function decorator(){
   return parent::decorator()."SEO加了";
  }
}
//现在这两个是平级的没有了继承 也不知道先后顺序 怎么办？
  
$BA = new BaseArt('天天向上');
 $BA->decorator();
  
$art = new BianArt('art');
echo $art->decorator()  
*/
class BianArt extends BaseArt{
  public function __construct(BaseArt $art){
    //普通文章传过来 自己调用自己给加上内容
    $this->art=$art;
    $this->decorator();
  }
  public function decorator(){
   //return parent::decorator()."小编加了摘要";
  return $this->content= $this->art->decorator()."小编加了摘要";
  }
}
class SeoArt extends BaseArt{
  public function __construct(BaseArt $art){
    //普通文章传过来 自己调用自己给加上内容
    $this->art=$art;
    $this->decorator();
  }
  public function decorator(){   
  return $this->content= $this->art->decorator()."seo优化";
  }
}   
$con = new BianArt(new BaseArt('con'));
echo $con->decorator(); 
//呵呵接下来有意思了就是new中new
// new BianArt（new BaseArt）
$con2 = new SeoArt(new BianArt(new BaseArt('con')));
echo $con2->decorator();
?>