jQuery progressbar通过Ajax请求实现后台进度实时功能

网络编程 2024/11/15 佚名

3 2 1

本文主要演示Jquery progressbar的进度条功能。js通过ajax请求向后台实时获取当前的进度值。后台将进度值存储在cookie中，每次请求后，将进度条的值增2个。以此演示进度条的实时显示功能。

前台index.jsp

jsp代码如下

<%@ 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"> -->
<!DOCTYPE html>
<html>
 <head>
 <base href="<%=basePath%>">

 <title>My JSP 'index.jsp' starting page</title>
 <link rel="stylesheet" type="text/css" href="js/themes/default/easyui.css">
 <link rel="stylesheet" type="text/css" href="js/themes/icon.css">
 <link rel="stylesheet" type="text/css" href="js/demo/demo.css">
 <script type="text/javascript" src="/UploadFiles/2021-04-02/jquery.min.js">

struts.xml文件的配置 


<"1.0" encoding="UTF-8" "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
 "http://struts.apache.org/dtds/struts-2.0.dtd">

<struts>
 <constant name="struts.devMode" value="true" />
 <package name="front" extends="struts-default" namespace="/">
  <action name="getProgressValueByJson" class="edu.njupt.zhb.test.TestAction" method="getProgressValueByJson">
   <result name="success"></result>
  </action>
  <action name="TestAction" class="edu.njupt.zhb.test.TestAction">
   <result type="httpheader"></result>
  </action>
 </package>

</struts>




后台的java代码（） 


package edu.njupt.zhb.test;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionSupport;
/*
 *@author: ZhengHaibo 
 *web:  http://blog.csdn.net/nuptboyzhb
 *mail: zhb931706659@126.com
 *Sep 13, 2013 Nanjing,njupt,China
 */
public class TestAction extends ActionSupport {
 /**
 * 
 */
 private static final long serialVersionUID = -8697049781798812644L;
 /**
 * 通过Ajax获取json格式的ProgressBar值
 * Type：Action
 */
 public void getProgressValueByJson(){
 String progressValueString = getCookie(getRequest(),"progressValue");
 int progressValue = Integer.parseInt(progressValueString);
 if(progressValue>100){
 progressValue = 0;
 }
 System.out.println(" getCookie:---progressValue="+progressValue);
 writeJsonString("{\"progressValue\":\"" + progressValue + "\"}"); 
 progressValue += 2;
 setCookie(getResponse(),"progressValue",progressValue+"",365*24*60*60);
 }
 
 /**
 * Get HttpServletRequest Object
 * @return HttpServletRequest
 */
 public HttpServletRequest getRequest(){
 return ServletActionContext.getRequest();
 }

 /**
 * Get HttpServletResponse Object
 * @return HttpServletResponse
 */
 protected HttpServletResponse getResponse() {
 return ServletActionContext.getResponse();
 }

 /**
 * Get PrintWriter Object
 * @return PrintWriter
 * @throws IOException
 */
 protected PrintWriter getWriter() throws IOException {
 return this.getResponse().getWriter();
 }

 /**
 * 写Json格式字符串
 * @param json
 */
 protected void writeJsonString(String json) {
 try {
 getResponse().setContentType("text/html;charset=UTF-8");
 this.getWriter().write(json);
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 
 /**
 * 获取cookie
 * @param request
 * @param name
 * @return String
 */
 public static String getCookie(HttpServletRequest request, String name) {
 String value = null;
 try {
 for (Cookie c : request.getCookies()) {
 if (c.getName().equals(name)) {
  value = c.getValue();
 }
 }
 } catch (Exception e) {
 e.printStackTrace();
 }
 return value;
 }
 
 /**
 * 设置cookie
 * @param response
 * @param name
 * @param value
 * @param period
 */
 public static void setCookie(HttpServletResponse response, String name, String value, int period) {
  try {
   Cookie div = new Cookie(name, value);
   div.setMaxAge(period);
   response.addCookie(div);

  } catch (Exception e) {
   e.printStackTrace();
  }
 }
}




运行


将项目部署到Tomcat上之后，在浏览器中输入URL，则可以看到进度条逐渐更新

源码下载：http://xiazai.jb51.net/201610/yuanma/jqueryProgressbar(jb51.net).rar
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。