jsp cookie+session实现简易自动登录_JSP编程_

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
 用户名：
<%--记住用户名 --%>
<% //读取session值 String val= (String)session.getAttribute("name"); //如果session不存在 if(val==null){ val ="不存在"; } out.print("当前\""+val+"\"用户可自动登录"); %>

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%><% //获取username String name = request.getParameter("username"); //判断用户名是否存在 if(name != null && !name.trim().equals("")){ //String[] time = request.getParameterValues("time"); //设置session值，(login页面可读取) session.setAttribute("name", name); //设置Cookie Cookie Cookie = new Cookie("name",name); Cookie.setMaxAge(30*24*3600); //设置cookie有效期为30天 response.addCookie(Cookie); //在客户端保存Cookie out.println("welcome: " + name+"欢迎登录"); } else{ response.sendRedirect("main.jsp"); } %>relogin

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%><% String name=(String)session.getAttribute("username"); //获取cookie Cookie[] cookies = request.getCookies(); //cookie存在 if(cookies != null && cookies.length > 0){ for(Cookie cookie:cookies){ //获取cookie的名字 String cookieName = cookie.getName(); //判断是否与name相等 if(cookieName.equals("name")){ //获取cookie的值 String value = cookie.getValue(); name = value; } } out.println("welcome again: " + name+"欢迎登录"); //************************* // 另一种写法 String v=null; for(int i=0;irelogin