CSS:

1.

<link type="text/css" href="<%=ResolveUrl("~/css/css.css")%>" rel="stylesheet"/> asp.net相对服务器路径

<link type="text/css" href="/css/css.css" rel="stylesheet"/>

2.

<style type="text/css">

.txtClass {

font-size: 12px;

}

</syle>

JS: 标签不能简写, 必须<script></script>

1.

<script type="text/javascript" src="<%=ResolveUrl("~/js/jquery-1.4.2.mini.js")%>" ></script> asp.net相对服务器路径

<script type="text/javascript" src="/js/jquery-1.4.2.mini.js" ></script>

2.

<script language="javascript" type="text/javascript">

function check_up_message(text)

{

}

</script>