Jsp+Servlet实现购物车功能

程序员文章站 2022-06-20 08:03:22

本文实例为大家分享了servlet实现购物车功能的具体代码，供大家参考，具体内容如下 (1)用servlet实现简单的购物车系统，项目结构例如以下：（新建web pr...

本文实例为大家分享了servlet实现购物车功能的具体代码，供大家参考，具体内容如下

(1)用servlet实现简单的购物车系统，项目结构例如以下：（新建web project项目仅仅须要additemservlet ， listitemservlet。exam403.jsp三个文件就可以。其它的不用管）

Jsp+Servlet实现购物车功能

（2）exam403.jsp代码例如以下：

<%@ page contenttype="text/html; charset=gb2312" language="java" import="java.sql.*" errorpage="" %>
<!doctype html public "-//w3c//dtd xhtml 1.0 transitional//en" "http://www.w3.org/tr/xhtml1/dtd/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="content-type" content="text/html; charset=gb2312" />
<title>无标题文档</title>
</head>

<body>
<form id="form1" name="form1" method="post" action="/servletproject/additem">
 <label></label>
 商品:
 <select name="itemid" id="itemid">
  <option value="洗衣粉">洗衣粉</option>
  <option value="香皂">香皂</option>
  <option value="食用油">食用油</option>
 </select>
 <p>数量:
  <label>
  <input name="quantity" type="text" id="quantity" value="1" />
  </label>
  <label>
  <input type="submit" name="submit" value="提交" />
  </label>
  <a href="/servletproject/listitem">查看购物车</a></p>
</form>
</body>
</html>

（3）additemservlet代码例如以下：

package com.lc.shoppingcar;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
public class additemservlet extends httpservlet 
{ 
 protected void doget(httpservletrequest request,httpservletresponse response)
             throws servletexception,java.io.ioexception
  {
   servletcontext application=getservletcontext() ;
   servletconfig config=getservletconfig() ;
   response.setcontenttype("text/html;charset=gb2312");
   printwriter out=response.getwriter(); 
   httpsession session =request.getsession();
   request.setcharacterencoding("gb2312");
   
   //读取表单传入的商品id及数量
   string id=request.getparameter("itemid"); 
 string num=request.getparameter("quantity");
 if(id!=null && num.length()!=0)
 { //从sessionn中读取购物车
 hashmap shoppingcar=(hashmap)session.getattribute("shoppingcar");
   if(shoppingcar==null)
    shoppingcar=new hashmap();
   //将商品加入到购物车中
   string onum=(string)shoppingcar.get(id);
   if(onum==null)
     shoppingcar.put(id,num);
   else
   {
    int n1=integer.parseint(num);
   int n2=integer.parseint(onum);
   string result=string.valueof(n1+n2);
   shoppingcar.put(id,result);
   }  
     //将购物车写回session中保存
   session.setattribute("shoppingcar",shoppingcar); 
  }
  else //假设传入的商品id号为空或数量为空。显示提示信息
   system.out.print("商品id号为空会或数量为空！");
  //返回商品列表页
  response.sendredirect("/servletproject/exam403.jsp");  
   } 
   
protected void dopost(httpservletrequest request,httpservletresponse response)
                throws servletexception,java.io.ioexception
 {
   doget(request,response);
  }
}

（4）listitemservlet代码例如以下：

package com.lc.shoppingcar;


import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
public class listitemservlet extends httpservlet 
{ 
 protected void doget(httpservletrequest request,httpservletresponse response)
             throws servletexception,java.io.ioexception
  {
   servletcontext application=getservletcontext() ;
   servletconfig config=getservletconfig() ;
   response.setcontenttype("text/html;charset=gb2312");
   printwriter out=response.getwriter(); 
   httpsession session =request.getsession();
   request.setcharacterencoding("gb2312");
   
    //从session中获取购物车
 hashmap shoppingcar=(hashmap)session.getattribute("shoppingcar");
  //显示购物车中的内容
  if(shoppingcar!=null)
  {
    set show=shoppingcar.entryset();
    iterator it=show.iterator();
    while(it.hasnext())
    {
     out.print(it.next()+"<br>");
    }
  }
  else
    out.print("购物车为空。"); 
   } 
   
protected void dopost(httpservletrequest request,httpservletresponse response)
                throws servletexception,java.io.ioexception
 {
   doget(request,response);
  }
}

（5）实现效果例如以下：

訪问：http://localhost:8080/servletproject/exam403.jsp 学则商品提交

Jsp+Servlet实现购物车功能