第八周作业
1.登陆
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"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>My JSP 'login.jsp' starting page</title> </head> <body> <form action="dologin.jsp" method="post" name="login"> 用户名：<input type="text" name="uname" size="20"><br> 密 码：<input type="password" name="upwd" size="20"><br> <input type="button" value="登录" onClick="validate()"> </form> <script type="text/javascript"> function validate() { if (login.uname.value == "") { alert("用户名不能为空!"); return; } if (login.upwd.value == "") { alert("密码不能为空!"); return; } login.submit(); } </script> </body> </html>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>My JSP 'dologin.jsp' starting page</title> </head> <body> <% //设置编码 request.setCharacterEncoding("UTF-8"); response.setCharacterEncoding("UTF-8"); //获取请求数据 String uname = request.getParameter("uname"); String upwd = request.getParameter("upwd"); //判断密码和用户名是否相同 if (uname.equals(upwd)) { session.setAttribute("uname",uname); request.getRequestDispatcher("main.jsp") .forward(request, response); } else { response.sendRedirect("no.jsp"); } %> </body> </html>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort() + path + "/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>My JSP 'loginout.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> <% session.invalidate(); response.setHeader("refresh", "5;url=login.jsp"); %> </body> </html>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>My JSP 'main.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="loginout.jsp">退出登录</a> </body> </html>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>My JSP 'no.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"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>My JSP 'main.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="loginout.jsp">退出登录</a> <br> <form action="Buy.jsp"> <hr> 是否加入购物车？<br> <input name="item" type="checkbox" value="weilong"> 山楂 $1<br> <input name="item" type="checkbox" value="xizhilang"> 薯片 $2<br> <input name="item" type="checkbox" value="menglong"> 雪糕 $3<br> <hr> <input type="submit" value="加入购物车"> </form> </body> </html>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>My JSP 'Buy.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> <h2>购物车</h2> <% request.setCharacterEncoding("utf-8"); String itemName[] = request.getParameterValues("item"); if (itemName == null) { out.print("购物车为空"); } else { for (int k = 0; k < itemName.length; k++) { out.print("(" + (k + 1) + ")" + itemName[k] + "<br>"); } } %> </body> </html>
