標籤：snippet app xhtml host 分享 oid rect red gravity
(1)用servlet實現簡單的購物車系統，項目結構例如以下：（建立web Project項目 僅僅須要AddItemServlet ， ListItemServlet。exam403.jsp三個檔案就可以。其它的不用管）
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（2）exam403.jsp代碼例如以下：
<%@ 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>無標題文檔</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>數量: <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">查看購物車</a></p></form></body></html>
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"); //讀取表單傳入的商品ID及數量 String id=request.getParameter("itemID"); String num=request.getParameter("quantity"); if(id!=null && num.length()!=0) { //從Sessionn中讀取購物車HashMap shoppingCar=(HashMap)session.getAttribute("shoppingCar"); if(shoppingCar==null) shoppingCar=new HashMap(); //將商品加入到購物車中 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); } //將購物車寫回session中儲存 session.setAttribute("shoppingCar",shoppingCar); } else //假設傳入的商品ID號為空白或數量為空白。顯示提示資訊 System.out.print("商品ID號為空白會或數量為空白！"); //返回商品列表頁 response.sendRedirect("/servletProject/exam403.jsp"); } protected void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException,java.io.IOException { doGet(request,response); }}
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"); //從session中擷取購物車HashMap shoppingCar=(HashMap)session.getAttribute("shoppingCar"); //顯示購物車中的內容 if(shoppingCar!=null) { Set show=shoppingCar.entrySet(); Iterator it=show.iterator(); while(it.hasNext()) { out.print(it.next()+"<br>"); } } else out.print("購物車為空白。"); } protected void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException,java.io.IOException { doGet(request,response); }}
訪問：http://localhost:8080/servletProject/exam403.jsp 學則商品 提交
點擊查看購物車：
OK！
簡單的購物車 到此結束！
Servlet/Jsp實現購物車
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