Thinkphp无限级分类代码

<?php
class CateAction extends Action{
function index(){
$cate=M('Cate');
$list=$cate->field("id,name,pid,path,concat(path,'-',id) as bpath")->order('bpath')->select();
foreach($list as $key=>$value){
$list[$key]['count']=count(explode('-',$value['bpath']));
}
$this->assign('alist',$list);
$this->display();
}//添加栏目
function add(){
$cate=new CateModel();if($vo=$cate->create()){
if($cate->add()){
$this->success('添加栏目成功');
}else{
$this->error('添加栏目失败');
}
}else{
$this->error($cate->getError());
}
}}
?>

<?php
class CateModel extends Model{//对应数据库中的表xp_cate
protected $_auto=array(
array('path','tclm',3,'callback'),
);function tclm(){
$pid=isset($_POST['pid'])?(int)$_POST['pid']:0;
echo ($pid);
if($pid==0){
$data=0;
}else{
$list=$this->where("id=$pid")->find();
$data=$list['path'].'-'.$list['id'];//子类的path为父类的path加上父类的id
}
return $data;
}
}
?>

<form action="/Article/add" method="post">
请选择父级栏目：<select name="pid" size="20">
<option value="0">根栏目</option>
<volist name="alist" id="vo">
<option value="{$vo['id']}">
<for start="0" end="$vo['count']">
  
</for>
{$vo['name']}
</option>
</volist>
</select><br />
新的栏目名称：<input type="text" name="name" /><br />
<input type="submit" value="添加栏目" />
</form>