PHP中如何獲取下拉選單的值

<?php

$q = isset($_GET['q'])? htmlspecialchars($_GET['q']) : '';

if($q) { if($q =='RUNOOB') {

echo '我的地址<br>czdg.zrghs.com';

} else if($q =='CHAXUN') {

echo '查詢<br>'sxyl.zrghs.com;

} else if($q =='XIANSHI') {

echo '顯示<br>cdxl.zrghs.com'; } }

else { ?>
<form action="" method="get">

<select name="q">

<option value="">選擇一個站點:</option>

<option value="RUNOOB">Runoob</option>

<option value="GOOGLE">Google</option>

<option value="TAOBAO">Taobao</option>

</select>

<input type="submit" value="提交"> </form>

?>