session购物车功能

时间:2022-05-23 一只小小的蚂蚁人气:0

一、实现的功能

（1）利用session实现购物车中的物品添加。
（2）使用servlet实现添加物品的功能（交互层）。
（3）一共有三个界面。第一个用来显示物品的列表的页面，第二个用来显示添物品的界面，第三个用来显示添加到购物车的信息页面。

二、代码实现

（1）物品列表页面：productlist.jsp

<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Insert title here</title>
</head>
<body>
    <a href="<%=request.getContextPath()%>/shopping.pdo?pname='LENOVO R7'">联想拯救者R7</a>
    <br><br>
    <a href="<%=request.getContextPath()%>/shopping.pdo?pname='LENOVO R8'">联想拯救者R8</a>
    <br><br>
    <a href="<%=request.getContextPath()%>/shopping.pdo?pname='LENOVO R9'">联想拯救者R9</a>
    <br><br>
    <a href="<%=request.getContextPath()%>/shopping.pdo?pname='LENOVO R10'">联想拯救者R10</a>
    <br><br>
</body>
</html>

（2）添加购物车页面：producttails.jsp

<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Insert title here</title>
</head>
<body>
        <%
            String pname = (String)request.getAttribute("p");
            out.println(pname);
        %>
        <br><br>
        拿到其他的......该产品的详细参数
        
        <br><br>
        <a style="display: block;width: 100px ; height: 35px ;line-height :35px; text-decoration : none;background: red; color:#fff ;text-align: center;" href="<%=request.getContextPath() %>/addcart.pdo?pname=<%=pname %>" >加入购物车</a>
</body>
</html>

（3）显示添加成功后的信息页面：shoppingcart.jsp

<%@page import="java.util.List"%>
<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Insert title here</title>
</head>
<body>
        <%
            List<String> products = (List<String>)session.getAttribute("car");
            for(String s: products){
                out.print(s+"<br><br>");
            }
        %>
</body>
</html>

（4）交互层：ShopController.java

package com.controller;

import java.io.IOException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

/**
 * Servlet implementation class ShopController
 */
@WebServlet(urlPatterns = {"*.pdo"})
public class ShopController extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ShopController() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        //设置字符集
        request.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("text/html; charset=utf-8");
        
        //在这个方法里边处理所有的增删改查的功能
        String mn = request.getServletPath();
        mn = mn.substring(1);
        mn = mn.substring(0 , mn.length()-4);
        
        //利用反射
        try {
            //获取方法名，并且根据具体的去调用下边的方法
            Method method = this.getClass().getDeclaredMethod(mn,HttpServletRequest.class , HttpServletResponse.class);
            method.invoke(this,request,response);
            
        } catch (NoSuchMethodException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    


    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doGet(request, response);
    }
    
    private void shopping (HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //设置字符集
        request.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("text/html; charset=utf-8");
        String pname = request.getParameter("pname");
        request.setAttribute("p", pname);
        request.getRequestDispatcher("/producttails.jsp").forward(request, response);;
    }
    
    private void addcart (HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //设置字符集
        request.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("text/html; charset=utf-8");
        
        String pname = request.getParameter("pname");
        //添加购物车
        HttpSession session = request.getSession(true);
        
        List<String> products = (List<String>)session.getAttribute("car");
        if(products == null) {
            products = new ArrayList<>();
        }
        //把添加的物品放入List集合
        products.add(pname);
        //放入session中表示添加成功
        session.setAttribute("car", products);
        
        //response.getWriter().print("添加成功！");
        response.sendRedirect(request.getContextPath() + "/shoppingcart.jsp");
    }
}

加载全部内容