PHP无限分类的类

<?php 
/** 
 * @author        YangHuan 
 * @datetime     
 * @version        1.0.0 
 */ 

/** 
 * Short description. 
 * 
 * Detail description 
 * @author        
 * @version      1.0 
 * @copyright     
 * @access       public 
 */ 
class Tree 
{ 
    /** 
     * Description 
     * @var        
     * @since     1.0 
     * @access    private 
     */ 
    var $data    = array(); 

    /** 
     * Description 
     * @var        
     * @since     1.0 
     * @access    private 
     */ 
    var $child    = array(-1=>array()); 

    /** 
     * Description 
     * @var        
     * @since     1.0 
     * @access    private 
     */ 
    var $layer    = array(-1=>-1); 

    /** 
     * Description 
     * @var        
     * @since     1.0 
     * @access    private 
     */ 
    var $parent    = array(); 

    /** 
     * Short description.  
     * 
     * Detail description 
     * @param      none 
     * @global     none 
     * @since      1.0 
     * @access     private 
     * @return     void 
     * @update     date time 
    */ 
    function Tree ($value) 
    { 
        $this->setNode(0, -1, $value); 
    } // end func 

    /** 
     * Short description.  
     * 
     * Detail description 
     * @param      none 
     * @global     none 
     * @since      1.0 
     * @access     private 
     * @return     void 
     * @update     date time 
    */ 
    function setNode ($id, $parent, $value) 
    { 
        $parent = $parent?$parent:0; 

        $this->data[$id]            = $value; 
        $this->child[$id]            = array(); 
        $this->child[$parent][]        = $id; 
        $this->parent[$id]            = $parent; 

        if (!isset($this->layer[$parent])) 
        { 
            $this->layer[$id] = 0; 
        } 
        else 
        { 
            $this->layer[$id] = $this->layer[$parent] + 1; 
        } 
    } // end func 

    /** 
     * Short description.  
     * 
     * Detail description 
     * @param      none 
     * @global     none  
     * @since      1.0 
     * @access     private 
     * @return     void 
     * @update     date time 
    */ 
    function getList (&$tree, $root= 0) 
    { 
        foreach ($this->child[$root] as $key=>$id) 
        { 
            $tree[] = $id; 

            if ($this->child[$id]) $this->getList($tree, $id); 
        } 
    } // end func 

    /** 
     * Short description.  
     * 
     * Detail description 
     * @param      none 
     * @global     none 
     * @since      1.0 
     * @access     private 
     * @return     void 
     * @update     date time 
    */ 
    function getValue ($id) 
    { 
        return $this->data[$id]; 
    } // end func 

    /** 
     * Short description.  
     * 
     * Detail description 
     * @param      none 
     * @global     none 
     * @since      1.0 
     * @access     private 
     * @return     void 
     * @update     date time 
    */ 
    function getLayer ($id, $space = false) 
    { 
        return $space?str_repeat($space, $this->layer[$id]):$this->layer[$id]; 
    } // end func 

    /** 
     * Short description.  
     * 
     * Detail description 
     * @param      none 
     * @global     none 
     * @since      1.0 
     * @access     private 
     * @return     void 
     * @update     date time 
    */ 
    function getParent ($id) 
    { 
        return $this->parent[$id]; 
    } // end func 

    /** 
     * Short description.  
     * 
     * Detail description 
     * @param      none 
     * @global     none 
     * @since      1.0 
     * @access     private 
     * @return     void 
     * @update     date time 
    */ 
    function getParents ($id) 
    { 
        while ($this->parent[$id] != -1) 
        { 
            $id = $parent[$this->layer[$id]] = $this->parent[$id]; 
        } 

        ksort($parent); 
        reset($parent); 

        return $parent; 
    } // end func 

    /** 
     * Short description.  
     * 
     * Detail description 
     * @param      none 
     * @global     none 
     * @since      1.0 
     * @access     private 
     * @return     void 
     * @update     date time 
    */ 
    function getChild ($id) 
    { 
        return $this->child[$id]; 
    } // end func 

     
    /** 
     * Short description.  
     * 
     * Detail description 
     * @param      none 
     * @global     none 
     * @since      1.0 
     * @access     private 
     * @return     void 
     * @update     date time 
    */ 
    function getChilds ($id = 0) 
    { 
        $child = array($id); 
        $this->getList($child, $id); 

        return $child; 
    } // end func 
} // end class 

?>

<?php
//new Tree(根目录的名字); 
//根目录的ID自动分配为0 
$Tree = new Tree('根目录'); 

//setNode(目录ID,上级ID，目录名字); 
$Tree->setNode(1, 0, '目录1'); 
$Tree->setNode(2, 0, '目录2'); 
$Tree->setNode(3, 0, '目录3'); 
$Tree->setNode(4, 3, '目录3.1'); 
$Tree->setNode(5, 3, '目录3.2'); 
$Tree->setNode(6, 3, '目录3.3'); 
$Tree->setNode(7, 2, '目录2.1'); 
$Tree->setNode(8, 2, '目录2.2'); 
$Tree->setNode(9, 2, '目录2.3'); 
$Tree->setNode(10, 6, '目录3.3.1'); 
$Tree->setNode(11, 6, '目录3.3.2'); 
$Tree->setNode(12, 6, '目录3.3.3'); 

//getChilds(指定目录ID); 
//取得指定目录下级目录.如果没有指定目录就由根目录开始 
$category = $Tree->getChilds(); 

//遍历输出 
foreach ($category as $key=>$id) 
{ 
    echo $Tree->getLayer($id, '|-').$Tree->getValue($id)."<br>\n"; 
}

<?php 
//无限分类，从子类找所有父类
//$id 子类ID
 function php100_xd($id){
   $sql="select * from fl where id='$id'";
   $q=mysql_query($sql);
   $rs=mysql_fetch_array($q);
   $rs['fid']==0 ? "" : fl($rs['fid']);
   echo $rs['name']."-";
   }

//读取所有父类下面的子类
//$f顶级分类从什么开始,$s样式
 function php100_dx($f=0,$s=""){
   $sql="select * from fl where fid=$f";
   $q=mysql_query($sql);
   $s=$s."-";
   while($rs=mysql_fetch_array($q)){
     echo "<br>$s".$rs['name'];
  flt($rs['id'],$s);
     } 
   }