当前位置: 首页 > 图文教程 > 网络编程 > AJAX技术 > AJAX 进度条实现代码

AJAX技术
AJAX 用户注册时的应用实例
ajax readyState的五种状态详解
php AJAX POST的使用实例代码
Ajax 用户名验证是否存在
Ajax+PHP简单基础入门实例教程
AJAX 异步传输数据的问题
ASP AJAX 静态分页
js装载xml文件然后发向服务器的实现代码
完成了AJAX树附原理分析
AJAX 支持搜索引擎问题分析
ajax Suggest类似google的搜索提示效果
Ajax 框架学习笔记
用ajax xml的数据读取的HelloWorld程序
Ajax 表单验证 实现代码
Ajax request response 乱码解决方法
AJAX 随记
ajax 乱码的一种解决方法
ajax session过期问题的几个解决方案
四步学会 Ajax
Ajax异步(请求)提交类 支持跨域

AJAX技术 中的 AJAX 进度条实现代码


出处:互联网   整理: 软晨网(RuanChen.com)   发布: 2009-10-13   浏览: 75 ::
收藏到网摘: n/a

AJAX 进度条实现代码,基于java后来,大家可以学习下。 效果如下:

复制代码 代码如下:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Ajax Progress Bar</title>
<script type="text/javascript">
var xmlHttp;
var key;
var bar_color = 'gray';//进度条的颜色
var span_id = "block";
var clear = " ";
function createXMLHttpRequest()//创建XMLHttpRequest对象
{
if(window.ActiveXObject)
{
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
else if(window.XMLHttpRequest)
{
xmlHttp = new XMLHttpRequest();
}
}
function go()
{
createXMLHttpRequest();//创建XMLHttpRequest对象
checkDiv();//显示滚动条
xmlHttp.onreadystatechange = callBack;//设置回调函数
var url = "/AjaxDemo/servlet/ProgressBarServlet?task=create";//请求的地址
var button = document.getElementById("go");
button.disabled = true;//设置按钮不可用
xmlHttp.open("get",url,true);//打开对服务器的连接
xmlHttp.send();//发送请求
}
function callBack()
{
if(xmlHttp.readyState == 4)
{
if(xmlHttp.status == 200)
{
setTimeout("pollServer()",500);//定时调用
}
}
}
function pollServer()
{
createXMLHttpRequest();
var url="/AjaxDemo/servlet/ProgressBarServlet?task=poll&key="+key;
xmlHttp.onreadystatechange = pollCallBack;
xmlHttp.open("GET",url,true);
xmlHttp.send();
}
function pollCallBack()
{
if(xmlHttp.readyState == 4)
{
if(xmlHttp.status == 200)
{
var percent_complete = xmlHttp.responseXML.getElementsByTagName("percent")[0]
.firstChild.data;//从服务器端获得响应信息
var index = processResult(percent_complete);
for(var i = 1; i<=index; i++)
{
var elem = document.getElementById("block"+i);
elem.innerHTML = clear;
elem.style.backgroundColor = bar_color;
var next_cell = i+1;
if(next_cell > index && next_cell <= 9)
{
document.getElementById("block"+next_cell).innerHTML = percent_complete + "%";
}
}
if(index <9 )
{
setTimeout("pollServer()",500);
}
else
{
document.getElementById("complete").innerHTML = "Complete!";
document.getElementById("go").disabled = false;
}
}
}
}
function processResult(percent_complete)
{
var ind;
if(percent_complete.length == 1)
{
ind = 1;
}
else if(percent_complete.length == 2)
{
ind = percent_complete.substring(0,1);
}
else
{
ind = 9;
}
return ind;
}
function checkDiv()
{
var progress_bar = document.getElementById("progressBar");
if(progress_bar.style.visibility == "visible")
{
clearBar();
document.getElementById("complete").innerHTML = "";
}
else
{
progress_bar.style.visibility = "visible";
}
}
function clearBar()
{
for(var i =1; i<10; i++)
{
var elem = document.getElementById("block"+i);
elem.innerHTML = clear;
elem.style.backgroundColor = "white";
}
}
</script>
</head>
<body>
<h1>Ajax Progress Bar Example</h1>
Launch long-running process:
<input type="button" value="Launch" id="go" onclick="go()"/>
<p>
<table align="center">
<tbody>
<tr>
<td>
<div id="progressBar" style="padding:2px;border:solid black 2px;visibility:hidden">
<span id="block1"> </span>
<span id="block2"> </span>
<span id="block3"> </span>
<span id="block4"> </span>
<span id="block5"> </span>
<span id="block6"> </span>
<span id="block7"> </span>
<span id="block8"> </span>
<span id="block9"> </span>
</div>
</td>
</tr>
<tr><td align="center" id="complete"></td></tr>
</tbody>
</table>
</body>
</html>

复制代码 代码如下:

package cn.Ajax.test;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@SuppressWarnings("serial")
public class ProgressBarServlet extends HttpServlet {
private int counter = 1;
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String task = request.getParameter("task");
String res="";
if(task.equals("create")){
res = "<key>1</key>";
counter = 1;
}
else{
String percent = "";
switch (counter) {
case 1: percent = "10";break;
case 2: percent = "23";break;
case 3: percent = "35";break;
case 4: percent = "51";break;
case 5: percent = "64";break;
case 6: percent = "73";break;
case 7: percent = "89";break;
case 8: percent = "100";break;
}
counter++;
res ="<percent>"+percent+"</percent>";
}
PrintWriter out = response.getWriter();
response.setContentType("text/xml");
response.setHeader("Cache-Control", "no-cache");
out.println("<response>");
out.println(res);
out.println("</response>");
out.close();
}
/**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}