Php无限级栏目分类读取的实现代码

<?php
 $query = $this->db->query("SELECT * FROM category");
 $list = $query->result();
 foreach($list as $v){
 if($v->category_id == 0){//获取父栏目(等于0的都是父栏目)
 $categoryul = anchor("home/content/".$v->id,$v->category_name);
 echo "<ul>".$categoryul."</ul>";
 $listx = $this->Listx->list_id($v->id);//在根据父id显示出指定的子栏目
 foreach($listx as $vid){

 $category = anchor("home/content/".$vid->id,$vid ->category_name);
 echo "<li>".$category."</li>";
   }
    }
  }
?>