PHP使用递归函数做多级下拉菜单

 <?php
    $t_result = get_tp($conn);
    $num = 0;
    while($t_rows = mysql_fetch_row($t_result)){
        echo "<div id=div".$num." style='position:relative; background-color:#DEEBEF; width:190; height:25; '>";
        echo "<span id=div".$num." class = Outline style='hand:hand;'></span>";
        echo "<label id=div".$num." class = Outline style='cursor:hand;'>";
        echo "<img src=images/jia.gif id=div".$num."img name=div".$num."img/>".$t_rows[0]."</label>";
        //输出二级菜单
        $sqlstr = "select * from tb_list where f_type='".$t_rows[0]."'";
        $result = mysql_query($sqlstr,$conn);
        echo "<div id=div".$num."details style=\"display:None; position:relative; left:35;\">";
        while($rows = mysql_fetch_row($result)){
            if($rows[4] == "0"){
                echo "<img src=images/folder.gif /><U><a href='".$rows[3]."?u_id=".$rows[0]."' target=mainFrame>".$rows[1]."</a></U>";
                echo "<br/>";
            }else{
                $bool = false;
                $g_list = explode(",",$rows[4]);
                for($i=0;$i<count($g_list);$i++){
                    if($_SESSION["u_group"] == $g_list[$i]){
                        $bool = true;
                        break;
                    }
                }
                if(@$rows[5] != "1"){
                    $p_list = explode(",",@$rows[5]);
                    for($i=0;$i<count($p_list);$i++){
                        if($_SESSION["u_name"] == $p_list[$i]){
                            $bool = true;
                            break;
                        }
                    }
                }
                if($bool){
                    echo "<img src=images/folder.gif /><U><a href='".$rows[3]."?u_id=".$rows[0]."' target=mainFrame>".$rows[1]."</a></U>";  
                    echo "<br/>";
                }
            }
        }
        echo "</div></div>";
        $num++; 
    }
?>  

代码有错误

那就认真调试一下，一定会找出问题所在的

一点一点调呗。
先把最里边的循环内容删掉，看能不能执行