//查询
 
$dsql->SetQuery("SELECT * FROM category ORDER BY sortorder ASC");
$dsql->Execute('parentlist');
$array = array();
$parentlist = array();
while ($rs=$dsql->getObject('parentlist'))
{
    if($rs->parentid == 0)
    {
        $parentlist[$rs->id] = (array)$rs;
    }
    else
    {
        $array[$rs->id] = (array)$rs;
    }
}
$parentlist = cat_options($parentlist, $array);  //我们求的结果数组
 
//$list父级分类的数组
 
//$array是除父级分类外的全部分类的数组
 
function cat_options(&$list,&$array)
{
    foreach ($list as $key => $arr)
    {
        foreach ($array as $k => $value)
        {
            if($value['parentid'] == $arr['id'])
            {
                $list[$key]['children'][] = $value;
                unset($array[$k]);
            }
        }
    }
    foreach ($list as $key => $arr)
    {
        if(is_array($arr['children']) && count($arr['children']) > 0)
        {
            $list[$key]['children'] = cat_options($list[$key]['children'], $array);
        }
    }
    return $list;
}

<?php   
//模拟PHP无限分类查询结果   
return array(   
array(   
‘id’=>1,   
‘pid’=>0,   
‘name’=>‘主页’   
),   
array(   
‘id’=>2,   
‘pid’=>0,   
‘name’=>‘新闻’   
),   
array(   
‘id’=>3,   
‘pid’=>0,   
‘name’=>‘媒体’   
),   
array(   
‘id’=>4,   
‘pid’=>0,   
‘name’=>‘下载’   
),   
array(   
‘id’=>5,   
‘pid’=>0,   
‘name’=>‘关于我们’   
),   
array(   
‘id’=>6,   
‘pid’=>2,   
‘name’=>‘天朝新闻’   
),   
array(   
‘id’=>7,   
‘pid’=>2,   
‘name’=>‘海外新闻’   
),   
array(   
‘id’=>8,   
‘pid’=>6,   
‘name’=>‘州官新闻’   
),   
array(   
‘id’=>9,   
‘pid’=>3,   
‘name’=>‘音乐’   
),   
array(   
‘id’=>10,   
‘pid’=>3,   
‘name’=>‘电影’   
),   
array(   
‘id’=>11,   
‘pid’=>3,   
‘name’=>‘小说’   
),   
array(   
‘id’=>12,   
‘pid’=>9,   
‘name’=>‘铃声’   
),   
array(   
‘id’=>13,   
‘pid’=>9,   
‘name’=>‘流行音乐’   
),   
array(   
‘id’=>14,   
‘pid’=>9,   
‘name’=>‘古典音乐’   
),   
array(   
‘id’=>15,   
‘pid’=>12,   
‘name’=>‘热门铃声’   
),   
array(   
‘id’=>16,   
‘pid’=>12,   
‘name’=>‘搞笑铃声’   
),   
array(   
‘id’=>17,   
‘pid’=>12,   
‘name’=>‘MP3铃声’   
),   
array(   
‘id’=>18,   
‘pid’=>17,   
‘name’=>‘128K’   
),   
array(   
‘id’=>19,   
‘pid’=>8,   
‘name’=>‘娱乐新闻’   
),   
array(   
‘id’=>20,   
‘pid’=>11,   
‘name’=>‘穿越类’   
),   
array(   
‘id’=>21,   
‘pid’=>11,   
‘name’=>‘武侠类’   
),   
);   
?>

<?php   
        
/**   
        
* Tree 树型类(无限分类)   
        

        
* @version 1.0   
        
* @access public    
* @example    
*   $tree= new Tree($result);   
        
*   $arr=$tree->leaf(0);   
        
*   $nav=$tree->navi(15);   
        
*/
        
class Tree {   
        
        private $result;   
        
        private $tmp;   
        
        private $arr;   
        
        private $already = array();   
        
        /**   
        
         * 构造函数   
        
         *    
         * @param array $result 树型数据表结果集   
        
         * @param array $fields 树型数据表字段，array(分类id,父id)   
        
         * @param integer $root 顶级分类的父id   
        
         */
        
        public function __construct($result, $fields = array('id', 'pid'), $root = 0) {   
        
                $this->result = $result;   
        
                $this->fields = $fields;   
        
                $this->root = $root;   
        
                $this->handler();   
        
        }   
        
        /**   
        
         * 树型数据表结果集处理   
        
         */
        
        private function handler() {   
        
                foreach ($this->result as $node) {   
        
                        $tmp[$node[$this->fields[1]]][] = $node;   
        
                }   
        
                krsort($tmp);   
        
                for ($i = count($tmp); $i > 0; $i--) {   
        
                        foreach ($tmp as $k => $v) {   
        
                                if (!in_array($k, $this->already)) {   
        
                                        if (!$this->tmp) {   
        
                                                $this->tmp = array($k, $v);   
        
                                                $this->already[] = $k;   
        
                                                continue;   
        
                                        } else {   
        
                                                foreach ($v as $key => $value) {   
        
                                                        if ($value[$this->fields[0]] == $this->tmp[0]) {   
        
                                                                $tmp[$k][$key]['child'] = $this->tmp[1];   
        
                                                                $this->tmp = array($k, $tmp[$k]);   
        
                                                        }   
        
                                                }   
        
                                        }   
        
                                }   
        
                        }   
        
                        $this->tmp = null;   
        
                }   
        
                $this->tmp = $tmp;   
        
        }   
        
        /**   
        
         * 反向递归   
        
         */
        
        private function recur_n($arr, $id) {   
        
                foreach ($arr as $v) {   
        
                        if ($v[$this->fields[0]] == $id) {   
        
                                $this->arr[] = $v;   
        
                                if ($v[$this->fields[1]] != $this->root) $this->recur_n($arr, $v[$this->fields[1]]);   
        
                        }   
        
                }   
        
        }   
        
        /**   
        
         * 正向递归   
        
         */
        
        private function recur_p($arr) {   
        
                foreach ($arr as $v) {   
        
                        $this->arr[] = $v[$this->fields[0]];   
        
                        if ($v['child']) $this->recur_p($v['child']);   
        
                }   
        
        }   
        
        /**   
        
         * 菜单 多维数组   
        
         *    
         * @param integer $id 分类id   
        
         * @return array 返回分支，默认返回整个树   
        
         */
        
        public function leaf($id = null) {   
        
                $id = ($id == null) ? $this->root : $id;   
        
                return $this->tmp[$id];   
        
        }   
        
        /**   
        
         * 导航 一维数组   
        
         *    
         * @param integer $id 分类id   
        
         * @return array 返回单线分类直到顶级分类   
        
         */
        
        public function navi($id) {   
        
                $this->arr = null;   
        
                $this->recur_n($this->result, $id);   
        
                krsort($this->arr);   
        
                return $this->arr;   
        
        }   
        
        /**   
        
         * 散落 一维数组   
        
         *    
         * @param integer $id 分类id   
        
         * @return array 返回leaf下所有分类id   
        
         */
        
        public function leafid($id) {   
        
                $this->arr = null;   
        
                $this->arr[] = $id;   
        
                $this->recur_p($this->leaf($id));   
        
                return $this->arr;   
        
        }   
        
}   
        
?>