jsp电子商务购物车实现之三购物车

用户9184480

发布于 2024-12-17 13:08:49

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代码可运行

文章被收录于专栏：云计算linux云计算linux

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代码可运行

CartServlet参考代码 :

public void doPost(HttpServletRequest req, HttpServletResponse resp)
      throws ServletException, IOException {

    String bookids[] = req.getParameterValues("bookId"); //id数组;

    Map<Integer,Book> cart = (Map<Integer,Book>)req.getSession().getAttribute("cart");
    //System.out.println(cart.size()); null对
    /*
     *     Integer   Book
     *     id        book  (count)       
     *     7         book  （count=2）
     *     8         book  ( count=5)
     * 
     * */

    BookDao bd = new BookDaoImpl();
    //如果购物车为null，则new出来一个HashMap对象
    if(cart==null){
      cart = new HashMap<Integer,Book>();//id以及book对象
      req.getSession().setAttribute("cart", cart);
    }

    for(String bookid:bookids){
      Book book = cart.get(Integer.parseInt(bookid));
      if(book==null){
        book = bd.findById(Integer.parseInt(bookid));//根据id获得书籍
        book.setCount(1);//数量为1
      }
      else{
        // 判断是否已经是最后一本书;数量大于获得数量,其他的不能再加数量了
        if(book.getStock()>book.getCount()){
          book.setCount(book.getCount()+1);
        }
      }
      cart.put(Integer.parseInt(bookid), book);
      //需要放入到数据库中,那么购物车表的字段是什么呢？
      //图书id 书名  图片名 数量 合计价格
    }

    req.getSession().setAttribute("cart", cart);
    resp.sendRedirect("cart.jsp");
  }

在该Servlet中利用了session进行存放值，就是开篇我们的方法之一，但是这种方法有什么问题呢？大家好好思考下！！！

下面是购物车代码参考：

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
  <head>
    <base href="<%=basePath%>">

    <title>My JSP 'cart.jsp' starting page</title>

  <meta http-equiv="pragma" content="no-cache">
  <meta http-equiv="cache-control" content="no-cache">
  <meta http-equiv="expires" content="0">    
  <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
  <meta http-equiv="description" content="This is my page">

  <link rel="stylesheet" href="css/style.css" type="text/css"></link>

  <script type="text/javascript" src="js/jquery-1.7.2.min.js"></script>

  <script type="text/javascript">
    function jian(id){
    if($("#count"+id).val()==1){
    //采用淘宝模式，如果低于1，则不用提示，直接不可用;
      $("#count"+id).prev().attribute("disabled","disabled");
      return;
    }

      $.ajax({
        url:'ChangeCartCountServlet',
        type:'post',
        dataType:'text',
        data:{
          bookid:id,
          count:parseInt($("#count"+id).val())-1   //  -1
        },
        success:function(data){

        var price = $("#price"+id).html();
          $("#count"+id).val(parseInt($("#count"+id).val())-1);
          $("#sum"+id).val("￥"+price*$("#count"+id).val());

          calcTotal();

        }
      });
    }

    function add(id){
      $.ajax({
        url:'ChangeCartCountServlet',
        type:'post',
        dataType:'text',
        data:{
          bookid:id,
          count:parseInt($("#count"+id).val())+1
        },
        success:function(data){
          if(data=="false"){
            alert("库存不足!!!!");        
          }
          else{
            var price = $("#price"+id).html();
            $("#count"+id).val(parseInt($("#count"+id).val())+1);
            $("#sum"+id).val("￥"+price*$("#count"+id).val());

            calcTotal();
          }
        }
      });




    }

    function calcTotal(){
      // input...
      var counts = $("input[id^=count]").toArray();  
      var prices = $("div[id^=price]").toArray();
      var total = 0;

      for(var i=0;i<prices.length;i++){
        total += prices[i].innerHTML*counts[i].value;
      }

      $("#total").val("￥"+total);
    }

  </script>

  </head>

  <body>
   <div id="header" class="wrap">
  <div id="banner"></div>
  <div id="navbar">
    <div class="userMenu">
      <ul>
        <li class="current"><font color="BLACK">欢迎您，<strong>andy</strong></font>   </li>
        <li><a href="index.html">首页</a></li>
        <li><a href="orderlist.html">我的订单</a></li>
        <li><a href="cart.html">购物车</a></li>
        <li><a href="logout.jsp">注销</a></li>
      </ul>
    </div>
  </div>
</div>
<div id="content" class="wrap">
  <div class="list bookList">
    <form method="post" name="shoping" action="BuyServlet">
      <table>
        <tr class="title">
          <th class="view">图片预览</th>
          <th>书名</th>
          <th class="nums">数量</th>
          <th class="price">价格</th>
          <th class="nums">合计</th>
          <th class="nums">操作</th>
        </tr>

          <c:set var="total" value="0"></c:set>

          <c:forEach items="${cart}" var="book">  
          <tr>

            <td class="thumb">
            <img src="images/book/${book.value.image}" /></td>
            <td class="title">${book.value.bookname}</td>
            <td>
            <img src="images/edit_jian.png" width="12" height="12" 
              οnclick="jian(${book.value.id})"/>

            <input id="count${book.value.id}" readonly="readonly"
              value="${book.value.count}" size="2"/>

            <img src="images/edit_add.png" width="12" height="12" 
                οnclick="add(${book.value.id})"/>
            </td>

            <td>￥
              <div id="price${book.value.id}" >${book.value.price}</div>
            </td>
            <td>
              <input id="sum${book.value.id}"
              value='<fmt:formatNumber 
                value="${book.value.count*book.value.price}"
                type="currency"></fmt:formatNumber>'
              />


              <c:set var="total" 
                value=
                "${total+book.value.count*book.value.price}"></c:set>

              <input type="hidden" name="items" value="10:2:31.6"/>
            </td>
            <td>
            <a href="DeleteCartItemServlet?bookid=${book.value.id}">删除</a>
            </td>
          </tr>
          </c:forEach>

        <tr>
          <td>
            地址
          </td>
          <td colspan="5">
            <input name="shipaddress">
          </td>
        </tr>
        <tr>
          <td>
            电话
          </td>
          <td colspan="5">
            <input name="contactphone">
          </td>
        </tr> 
        <tr><td colspan="5">

      <div class="button">
        <h4>总价：
          <input id="total" 
            value='<fmt:formatNumber value="${total}" type="currency"></fmt:formatNumber>'
          />
        元</h4>
        <input type="hidden" id="hidden_total_price" name="hidden_total_price"/>
        <input class="input-chart" type="submit" name="submit" value="" />
      </div>
      </td></tr>

      </table>
    </form>
  </div>
</div>
</body>
  <div id="footer" class="wrap">
    网上书城 &copy; 版权所有
  </div>
</html>



</html>

根据id从购物车中删除的Servlet代码参考如下：

protected void doGet(HttpServletRequest req, HttpServletResponse resp)
      throws ServletException, IOException {
    int bookid = Integer.parseInt(req.getParameter("bookid"));

        Map<Integer,Book> cart = (Map<Integer,Book>)
          req.getSession().getAttribute("cart");
        // 根据key(bookid)删除
        cart.remove(bookid);

        req.getSession().setAttribute("cart", cart);

        resp.sendRedirect("cart.jsp");
  }

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原始发表：2022-03-16，如有侵权请联系 cloudcommunity@tencent.com 删除

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