点击提交表单按钮变成提交中非可点状态！

代码：

<form method="get" action="" target="box">
<input id="buttonid" type="submit" value="提交" />
</form>
<script type="text/javascript" src="./js/jquery.js"></script>
<script>
$("form").submit(function() {
  $("#buttonid").val("正在处理...");
  $("#buttonid").attr("disabled", "disabled");
});
</script>