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"%>
<%
    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>
<title>My JSP 'index.jsp' starting page</title>
</head>

<body bgcolor=#ccffcc>
    <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="index1.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"%>
<%
    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>
<title>My JSP 'index.jsp' starting page</title>
</head>

<body >
    <%
        request.setCharacterEncoding("utf-8");
        String uname = request.getParameter("uname");
        String upwd = request.getParameter("upwd");
        if (uname.equals(upwd)) {
            session.setAttribute("uname", uname);
            request.getRequestDispatcher("index2.jsp").forward(request,
                    response);
        } else {
            response.sendRedirect("index3.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>
<title>My JSP 'index.jsp' starting page</title>
</head>

<body bgcolor=#FFccff>
    <%
        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("index.jsp");
    %>
    欢迎你<%=uname%><br>
    <br>
    <a href="index4.jsp">退出登录</a>
</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>
    <title>My JSP 'index.jsp' starting page</title>
  </head>
  
  <body bgcolor=#bgcclo>
    <h1>登陆失败!!</h1>
    <%response.setHeader("refresh", "5;url=index.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>
<title>My JSP 'index.jsp' starting page</title>
</head>

<body>
    <%
        session.invalidate();
        response.setHeader("refresh", "5;url=index.jsp");
    %>
    <h1>退出登录成功!</h1>
</body>
</html>

  

 

 

 

 

 

 2.购物车
和上一题一起,在main.jsp中做一个商品展示,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show.jsp 。(选作:在购物车show.jsp中加删除按钮删除商品)

<%@ 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>
<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%><br>
    <br>
    <a href="index4.jsp">退出登录</a>
    <hr>
    商品展示:
    <br> 欢迎进入水果商城:
    <br>
    <hr>
    <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="香蕉">
        香蕉 9.99/kg<br> <input type="checkbox" name="list" value="火龙果">
        火龙果 6.88/kg<br> <input type="checkbox" name="list" value="榴莲">
        榴莲 7.99/kg<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>
<title>My JSP 'index.jsp' starting page</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>

  

 

 

 

 

posted on 2022-04-24 13:41  李昌璇  阅读(6)  评论(0编辑  收藏  举报