<form action="__URL__/add" method="post">
栏目<select name="fid" size=20>
<option value="0">栏目</option>
<volist name='list' id='vo'>
<option value="{$vo['id']}">
{$vo['blank']}{$vo['name']}</option>
</volist>
</select><br/>
添加栏目:<input type="text" name='name'/><br/>
<input type="submit" value="添加"/>　
</form>

<?php
class IndexAction extends Action
{
/**
+----------------------------------------------------------
* 默认操作
+----------------------------------------------------------
*/
public function index(){
$Column=new ColumnModel();
$list=$Column->field("id,name,fid,sort,concat(sort,'-',id) nsort")->order('nsort asc')->select();
foreach($list as $key=>$val){
$layer=count(explode('-',$list[$key]['nsort']));
$list[$key]['blank']='';
for($i=0;$i<$layer;$i++){
if($i==$layer-1){
$list[$key]['blank'].='---|';
}else{
$list[$key]['blank'].='---';
}
}
}
$this->assign('list',$list);
$this->display();
}
public function add(){
$Column=new ColumnModel;
$Column->create();
if($Column->add()){
$this->success('添加成功');
}else{
$this->error($Column->getError());
}
} 
} 
?>

<?php
class ColumnModel extends Model{
protected $_auto=array(
array('name','trim',0,'function'),//过滤用户不小心输入的空白字符
array('sort','createsort',0,'callback'),
);
/*
*自动完成sort字段
*根据POST过来的fid来查询上级sort，以确定本级sort
*/
protected function createsort(){
$fid=$_POST['fid']?(int)$_POST['fid']:0;//如果用户没有选择父栏目，则默认父栏目id为0
if($fid!='0'){
$list=$this->where("id=$fid")->find();
$data=$list['sort'].'-'.$fid;
}else{
$data='0';
}
return $data;
}
}
?>