不要缓存
<%
response.addHeader("Cache-Control","no-cache");
response.addHeader("Expires","Thu,01 Jan 1970 00:00:01 GMT");
%>
?
?<meta http-equiv="pragma" content="no-cache">
?<meta http-equiv="cache-control" content="no-cache">
?<meta http-equiv="expires" content="0">???