日期:2014-05-16  浏览次数:20595 次

ajax+servlet实现进度条
   业务逻辑:在web应用建立进度条。

    页面:progressBar.jsp

<%@ page contentType="text/html; charset=GBK" %>
<html>
<head>
<title>
Ajax进度条
</title>
<script type="text/javascript">
//xmlHttpRequest对象
var xmlHttp;
var key;
        //进度条颜色
        var bar_color='gray';
  var span_id='block';
         var clear="&nbsp;&nbsp;&nbsp;"
        
        //创建xmlHttpRequest对象
        function createXMLHttpRequest(){
         if (window.ActiveXObject){
          xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
                }
                else if(window.XMLHttpRequest){
                 xmlHttp = new XMLHttpRequest();
                }
        }
       
        //执行方法
        function go(){
         createXMLHttpRequest();
                checkDiv();
                var url = "ProgressBarServlet?task=create";
                //隐藏按钮
                var button = document.getElementById("go");
                button.disabled = true;
               
                xmlHttp.open("GET",url,true);
                xmlHttp.onreadystatechange = goCallback;
                xmlHttp.send(null);
        }
       
        //回调方法
        function goCallback(){
         if (xmlHttp.readyState == 4){
          if (xmlHttp.status == 200){
                           //设置更新时间
                                setTimeout("pollServer()",2000);
                        }
                }
        }
       
&nbs