Dynamic Dropdowns POST

Question

我試圖發佈從每個下拉菜單中獲得的值，這是一個n級別，但是我將使用它們的最大值爲3.我如何發佈每個我得到的值每個選擇？

<?php 

    include('dbcon.php'); 

    if($_REQUEST) 
    { 
$id  = $_REQUEST['parent_id']; 

$query = "select * from ajax_categories where pid = ".$id; 
$results = @mysql_query($query); 
$num_rows = @mysql_num_rows($results); 
if($num_rows > 0) 
{?> 
    <select name="sub_category" class="parent"> 
    <option value="" selected="selected">-- Sub Category --</option> 
    <?php 
    while ($rows = mysql_fetch_assoc(@$results)) 
    {?> 
     <option value="<?php echo $rows['id'];?>"><?php echo $rows['category'];?></option> 
    <?php 
    }?> 
    </select> 
<?php 
} 
else{echo '<label style="padding:7px;float:left; font-size:12px;">No Record Found !</label>';} 
    } 

    ?> 

http://www.99points.info/2010/12/n-level-dynamic-loading-of-dropdowns-using-ajax-and-php/