登录注册：
<%@ page language="java" import="java.util.*" pageEncoding="GB2312"%>
<html>
<body>
<%
request.setCharacterEncoding("GB2312");
String username=request.getParameter("username");
String password=request.getParameter("password");
String sql="select * from user where username=? and password=?";
pstm=conn.prepareStatement(sql);
pstm.setString(1,username);
pstm.setString(2,password);
rs=pstm.executeQuery();
if(rs.next())
{
session.setAttribute("id",rs.getInt("userid"));
int id=rs.getInt("userid");
session.setAttribute("username",rs.getString("username"));
session.setAttribute("realname",rs.getString("realname"));
session.setAttribute("address",rs.getString("address"));
session.setAttribute("phone",rs.getString("phone"));
}
Integer userid=(Integer)session.getAttribute("id");
// System.out.println(userid);
if(userid==null)
{
%>
<table border=1>
<form action="" method="post">
<tr><td>用户名：</td><td><input type="text" name="username"></td></tr>
<tr><td>密 码：</td><td><input type="password" name="password"></td></tr>
<tr>
<td colspan="2" align="center"><input type="submit" value="登录" name="submit">
<a href="front/addUser.jsp">注册</a></td>
</tr>
</form>
</table>
<% }
else
{%>
<table border=1>
<tr><td><%= session.getAttribute("username")%>欢迎光顾我的书店</td></tr>
<tr><td><a href="front/updateUser.jsp?userid=<%=userid %>">修改个人信息</a></td></tr>
<tr><td><a href="front/SelectShoppingCart.jsp">查看购物车</a></td></tr>
<tr><td><a href="front/exit.jsp">退出</a></td></tr>
</table>
<%}
%>
</body>
</html>
购物车部分代码：
<%@ page language="java" import="java.util.*,com.javabean.*" pageEncoding="GB2312"%>
<%
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>
</head>
<body><center>
<a href="front/index.jsp"><img src="images/logo.gif" alt="" title="" border="0" /></a>
<%@ include file="menu.jsp"%>
<%@ include file="/DB.jsp" %>
<%@ include file="leftmenu.jsp"%> <table>
<tr>
<td colspan="8" id=s align="center"><h1>您的购物车</h1></td><br>
</tr>
<tr>
<td align="center">id</td><td align="center">名称</td><td align="center">作者</td>
<td align="center">出版社</td><td align="center">单价</td><td align="center">数量</td>
<td align="center">总价</td><td align="center">操作</td>
</tr>
<%
int totalNum=0;
double totalMoney=0.0;
ArrayList <ShoppingCartObject> cart=(ArrayList)session.getAttribute("shoppingcart");
Iterator it =null;
if(cart!=null && cart.size()>0){
it=cart.iterator();
while(it.hasNext()){
ShoppingCartObject sco=(ShoppingCartObject)it.next();
totalNum=totalNum+sco.getBooknum();
totalMoney=totalMoney+sco.getSubmoney();
%>
<tr>
<td align="center"><%=sco.getId() %></td>
<td align="center"><%=sco.getName() %></td>
<td align="center"><%=sco.getAuthor()%></td>
<td align="center"><%=sco.getPublisher() %></td>
<td align="center"><%=sco.getUnitprice() %></td>
<td align="center"><%=sco.getBooknum() %></td>
<td align="center">￥<%=sco.getSubmoney() %>元</td>
<td align="center"><a href="front/DelFromShoppingCart.jsp?id=<%=sco.getId()%>">删除</a>
<a href="front/bookdetail.jsp?id=<%=sco.getId()%>">详细信息</a></td>
</tr>
<%
}
}
else{ %>
<tr><td colspan="8" align="right">您一共买了<%= totalNum%>本书 总价为￥<%=totalMoney %>元</td></tr>
<tr><td colspan="8" align="center">您的购物车为空</td></tr><%} %>
<tr><td colspan="1" align="center"><a href="front/ClearShoppingCart.jsp">清空购物车</a></td>
<td colspan="4" align="center"><a href="front/allbook.jsp">继续购物</a></td>
<td colspan="3" align="center"><a href="front/makeorder.jsp">前往结账</a></td>
</tr>
</table>
</body>
</html>
</body>
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