第8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。
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

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<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<!DOCTYPE HTML >
<html>
<head>
<title>My JSP 'index.jsp' starting page</title>
</head>
<body>
    <script>
        function yz() {
            if (form.user.value == "") {
                alert('用户名不能为空');
                return;
            }
            if (form.password.value =="") {
                alert('密码不能为空');
                return;
            }
            form.submit();
        }
    </script>
    <form action="index.jsp" method="post" name="form">
        <table>
            <tr>
                <td>用户名：</td>
                <td><input type="text" name="user"></td>
            </tr>
            <tr>
                <td>密码：</td>
                <td><input type="password" name="password"></td>
            </tr>
            <tr>
                <td><input type="button" value="登录" onclick="yz()"></td>
            </tr>
        </table>
    </form>
</body>
</html>　
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<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<!DOCTYPE HTML >
<html>
<head>
<title>My JSP 'index.jsp' starting page</title>
</head>
<body>
    <%
        String user = request.getParameter("user");
        String password = request.getParameter("password");
        if (user.equals(password)) {
            session.setAttribute("user", user);
            request.getRequestDispatcher("index1.jsp").forward(request,
                    response);
        } else {
            response.sendRedirect("Copy of index.jsp");
        }
    %>
</body>
</html>　
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<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<!DOCTYPE HTML >
<html>
<head>
<title>My JSP 'index.jsp' starting page</title>
</head>
<body>
    <%
        String user = (String) session.getAttribute("user");
        if (user == null) {
            response.sendRedirect("Copy of index.jsp");
        }
    %>
    欢迎你<%=user%>
    <a href="index2.jsp">退出登录</a>
    <form action="index3.jsp" method="post">
 
        <table border="1" cellpadding="0" cellspacing="0" width="500">
 
            <thead>
                <tr>
                    <th>商品名称</th>
                    <th>价格</th>
                    <th>加购</th>
                </tr>
            </thead>
            <tbody>
                <tr>
                    <td>方便面</td>
                    <td>3</td>
                    <td align="center"><input type="checkbox" name="sp" value="方便面">
                    </td>
                </tr>
                <tr>
                    <td>元气森林</td>
                    <td>5</td>
                    <td align="center"><input type="checkbox" name="sp" value="元气森林">
                    </td>
                </tr>
                <tr>
                    <td>面包</td>
                    <td>4</td>
                    <td align="center"><input type="checkbox" name="sp" value="面包">
                    </td>
                </tr>
                <tr>
                    <td colspan="3"><input type="submit" value="加购">
                    </td>
                </tr>
            </tbody>
        </table>
    </form>
</body>
</html>
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<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<!DOCTYPE HTML >
<html>
<head>
<title>My JSP 'index.jsp' starting page</title>
</head>
<body>
    <%
        session.invalidate();
        response.sendRedirect("Copy of index.jsp");
    %>
</body>
</html>
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<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<!DOCTYPE HTML >
<html>
<head>
<title>显示购物车</title>
</head>
<body>
    <%
        request.setCharacterEncoding("utf-8");
        String[] sp = request.getParameterValues("sp");
        for (int i = 0; sp != null && i < sp.length; i++) {
            out.print(sp[i] + "<br>");
        }
    %>
</body>
</html>

 

 

 

posted @ 2022-04-24 20:48  医不活  阅读(20)  评论(0)    收藏  举报