session的典型案例一:使用session實現購物車
阿新 • • 發佈：2019-02-05
使用session實現購物車
step1.jsp:
step2.java:<%@ 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>商品列表</title> </head> <body> <h4>商品列表</h4> <form action="<%=basePath%>servlet/step2" method="post"> <table border="1px"> <tr> <td>商品名稱</td> <td>選擇</td> </tr> <tr> <td>java</td> <td><input type="checkbox" name="book" value="java"></td> </tr> <tr> <td>c</td> <td><input type="checkbox" name="book" value="c"></td> </tr> <tr> <td>c++</td> <td><input type="checkbox" name="book" value="c++"></td> </tr> </table> <input type="submit" value="確認"> </form> </body> </html>
step2.jsp:package com.sa.shopping; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; public class step2 extends HttpServlet { public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException{ //1.獲取選中的商品資訊 String[] books=request.getParameterValues("book"); //2.將商品放入session HttpSession session=request.getSession(); session.setAttribute("book", books); //3.重定向到step2 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+request.getContextPath()+"/"; response.sendRedirect(basePath+"/shopping/step2.jsp"); } }
step3.java:<%@ 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 'step1.jsp' starting page</title> </head> <body> <h4>填寫收件人，地址</h4> <form action="<%=basePath%>servlet/step3" method="post"> 收件人:<input type="text" name="receiver"><br> 地址:<input type="text" name="addr"><br> <input type="submit" value="提交"> </form> </body> </html>
package com.sa.shopping;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
public class step3 extends HttpServlet {
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String receiver=request.getParameter("receiver");
String addr=request.getParameter("addr");
HttpSession session=request.getSession();
session.setAttribute("receiver", receiver);
session.setAttribute("addr", addr);
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+request.getContextPath()+"/";
response.sendRedirect(basePath+"/shopping/step3.jsp");
}
}
<%@ 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 'step1.jsp' starting page</title>
</head>
<body>
<h4>資訊總覽</h4>
<form action="<%=basePath%>servlet/pay" method="post">
<%String[] books=(String[])session.getAttribute("book"); %>
商品:<%=Arrays.asList(books) %><br>
收件人:<%=session.getAttribute("receiver") %><br>
地址:<%=session.getAttribute("addr") %><br>
<input type="submit" value="付款">
</form>
</body>
</html>
