JSP第8周作业
1.输入用户名密码，判断用户名和密码相同，登陆成功，session中保存用户的用户名，进入主页main.jsp，主页有一个退出按钮，点击，回到登陆页login.jsp。要求：退出登录后，如果在浏览器直接输入主页main.jsp，访问不了，直接跳到登陆页
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <html> <head> <title>My JSP 'index.jsp' starting page</title> </head> <body> <script type="text/javascript"> function validate(){ if(loginForm.uname.value==""){ alert("账号不能为空!"); return; } if(loginForm.upwd.value==""){ alert("密码不能为空!"); return; } loginForm.submit(); } </script> <form name="loginForm" action="dologin.jsp" method="post"> 用户名:<input type="text" name="uname" ><br> 密码: <input type="password" name="upwd" > <input type="button" value="登录" onClick="validate()"> </form> </body> </html>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <html> <head> <title>My JSP 'index.jsp' starting page</title> </head> <body> <% String uname=(String)session.getAttribute("uname"); //如果他是空，说明没登陆，直接访问该页面了 if(uname==null) response.sendRedirect("login.jsp"); %> 欢迎你<%=uname %> <a href="logout.jsp">退出登录</a> </body> </html>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <% request.setCharacterEncoding("utf-8"); String uname = request.getParameter("uname"); String upwd = request.getParameter("upwd"); if (uname.equals(upwd)){ //转发到ok页面,但是url没变 session.setAttribute("uname", uname); request.getRequestDispatcher("main.jsp").forward(request,response); } else{ //重定向回login.jsp，浏览器url也变 response.sendRedirect("no.jsp"); }
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <html> <head> <title>My JSP 'index.jsp' starting page</title> </head> <body> <% session.invalidate(); response.setHeader("refresh", "5;url=login.jsp"); %> 退出登录成功 </body> </html>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <html> <head> <title>My JSP 'index.jsp' starting page</title> </head> <body> <h1>登陆失败！！</h1> <%response.setHeader("refresh", "5;url=login.jsp");%> </body> </html>
2.购物车
和上一题一起，在main.jsp中做一个购物车，里面显示3个商品名和价格 每一个后面有一个加入购物车按钮，main.jsp中有一个按钮（或者超链接）可以显示购物车。（选作：在购物车中加删除按钮删除商品）
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <html> <head> <title></title> </head> <body> <% String uname = (String) session.getAttribute("uname"); if (uname == null) response.sendRedirect("login.jsp"); %> 商品展示： <br> 欢迎购买玩具： <br> <form action="show.jsp" method="post"> 请选择要加入购物车的商品：<br> <input type="checkbox" name="list" value="荔枝" <br> <input type="checkbox" name="list" value="桃子"> <br> <input type="checkbox" name="list" value="西瓜"> <br> <input type="submit" value="加入购物车"> </form> </body> </html>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <html> <head> <title></title> </head> <body> <h2>购物车添加的商品有：</h2> <% request.setCharacterEncoding("utf-8"); String listName[] = request.getParameterValues("list"); if (listName == null) { out.print("购物车为空！"); } else { for (int i = 0; i < listName.length; i++) { out.print("(" + (i + 1) + ")" + listName[i] + "<br>"); } } %> </body> </html>
