<?php
if($_POST["submit"]){
$contents = $_POST['contents'];
echo $contents;
}?>
<form method="post">
<select name="contents">
<option value="No" selected="">不是傻逼</option>
<option value="Yes" selected="">我是傻逼</option>
</select>
<input type="submit" name="submit" value="提交" />
</form>