下拉式功能表-求php兩個下拉式清單聯動解決辦法.

php下拉式功能表資料庫

選擇科室後，對應員工姓名根據選擇的科室擷取，怎麼做到。
兩個列表的代碼：

```

echo "-請選擇-  ";
@include "conn.php"; //連結資料庫
$gzh_num_result=mysql_query("select gzh_num , gzh_name from gongzhong where gzh_renum=0 order by gzh_num ;");
while($gzh_num_row=mysql_fetch_array($gzh_num_result))
{

list($gzh_num,$gzh_name)=$gzh_num_row;

    echo "".$gzh_name."  ";        //  echosuboption($gzh_num,@$_GET['gzh_num']);};?>               echo "-請選擇-  ";      ".$yg_name."  ";};?>

