该购物过程是在session范围内完成的，需要使用session对象实现信息的共享
（1）购买“肉类”商品的页面
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<html>
<head>
<title>购物肉类商品页面</title>
</head>
<body>
<% request.setCharacterEncoding("UTF-8");
if(request.getParameter("c1")!=null)
session.setAttribute("s1",request.getParameter("c1"));
if(request.getParameter("c2")!=null)
session.setAttribute("s2",request.getParameter("c2"));
if(request.getParameter("c3")!=null)
session.setAttribute("c3",request.getParameter("c3"));
%>
各种肉类大甩卖，一律十块：<br>
<form method="post" action="ch03_18_buy1.jsp">
<p><input type="checkbox" name="c1" value="猪肉">猪肉
<input type="checkbox" name="c2" value="牛肉">牛肉
<input type="checkbox" name="c3" value="羊肉">羊肉
</p>
<p><input type="submit" value="提交" name="B1">
<a href="ch03_18_buy2.jsp">买点别的</a>
<a href="ch03_ 18_display.jsp">查看购物车</a>
</p>
</form>
</body>
</html>
（2）购买“球类”商品的页面
<%@page language="java" import="java.util.*" pageEncoding="UTF-8" %>
<html>
<head>
<title>购买球类页面</title>
</head>
<body>
<%request.setCharacterEncoding("UTF-8");
if(request.getParameter("b1")!=null)
session.setAttribute("s4",request.getParameter("b1"));
if(request.getParameter("b2")!=null)
session.setAttribute("s5",request.getParameter("b2"));
if(request.getParameter("b3")!=null)
session.setAttribute("s6",request.getParameter("b3"));
%>
各种球大甩卖，一律八块：
<form method="post" action="ch03_18_buy2.jsp">
<p>
<input type="checkbox" name="b1" value="篮球">篮球
<input type="checkbox" name="b2" value="足球">足球
<input type="checkbox" name="b3" value="排球">排球
</p>
<p>
<input type="submit" name="x1"value="提交">
<a href="ch03_18_buy1.jsp">买点别的</a>
<a href="ch03_18_buy2.jsp">查看购物车</a>
</form>
</body>
</html>
（3）显示购物车信息的页面
<%@page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<html>
<head>
<title>显示购物车购物信息</title>
</head>
<body>
你的选择结果是：<br>
<%request.setCharacterEncoding("UTF-8");
String str="";
if(session.getAttribute("s1")!=null)
{
str=(String)session.getAttribute("s1");
out.println(str+"<br>");
}
if(session.getAttribute("s2")!=null);
{
str=(String)session.getAttribute("s2");
out.print(str+"<br>");
}
if(session.getAttribute("s3")!=null)
{
str=(String)session.getAttribute("s3");
out.print(str+"<br>");
}
if(session.getAttribute("s4")!=null)
{
str=(String)session.getAttribute("s4");
out.print(str+"<br>");
}
if(session.getAttribute("s5")!=null)
{
str=(String)session.getAttribute("s5");
out.print(str+"<br>");
}
if(session.getAttribute("s6")!=null)
{
str=(String)session.getAttribute("s6");
out.print(str+"<br>");
}
%>
</body>
</html>