session.isNew():Returns true if the client does not yet know about the session or if the client chooses not to join the session. For example, if the server used only cookie-based sessions, and the client had disabled the use of cookies, then a session would be new on each request.
再次登陆时重新输入了用户密码,成功后就又保存到session中了啊
注销session.removeAttribute("userid");
implements HttpSessionListerner
sessionCreated session.setAttribute("userId","1111111");
sessionDestroyed session.inValidate();
if (session.isNew()) {
String userid=(String)session.getAttribute("userid");
System.out.print(userid);
if(userid==null||userid.equals("")){
%>
<SCRIPT language=JavaScript>
alert("对不起,您还没有登录,请先登陆!");
top.location.href="index.jsp";
</SCRIPT>
<%
}
} 可以追踪你的userid看看。
应该是isNew()这里在不关闭页面的时候session不会去掉
%>
登陆成功时用session.setAttribute("userid",userid);将usrid放入session中,然后在每个页面开始都用下面这段话判断是否有效,
<%
if (session.getAttribute("userid") == null) {
String userid=(String)session.getAttribute("userid");
}else{
%>
<SCRIPT language=JavaScript>
alert("对不起,您还没有登录,请先登陆!");
top.location.href="index.jsp";
</SCRIPT>
<%
}
%>
取值吗