最近做项目中遇到很多问题,比如带进度条的文件上传,看了网上很多资料还没找到真正意义上的ASP.NET实现进度条上传(可能是我没找到),下面我来跟大家分享一下我实现的这个程序。
首先看下界面效果,当然你可以完全修改界面为你自己所用。

先解释一下这个程序,该程序采用了jquery框架,实现了小文件上传,不超过80Mb,可以在web.config文件中进行相应的配置,但是有个最大值,具体需要查看msdn。开发环境采用visual studio 2013 .net framework 4.5,运行的时候大家注意一下是否满足要求,好了,下面直入正题。
先来看看实现原理。基本原理:一个页面进行文件上传,另外一个页面去监听这个文件上传了多少。
这里面有两个地方需要解释一下:第一个,如何知道监听的这个文件就是上传的这个文件?实现机制很简单,就是让asp.net产生一个唯一的guid,这个id序号是唯一的,通过ajax取出来赋值给一个隐藏字段;第二个,如何获取guid标志的文件信息?通过asp.net缓存机制实现,上传的过程中,不断的将上传信息往缓存里面写,直到文件上传完成,而在另外一个通过guid获取缓存的信息,信息包括你想要的信息,比如上传了多少字节、消耗了多长时间等。好了,要点就解释到这里,有疑问的话给我留言。
下面来说说具体的实现:
文件目录结构如下:

index.htm就是文件上传页面,提交form给UploadHandler目录下的Default.aspx,以实现文件上传。
ProgressHandler目录下三个文件为Abort.ashx、GenericGuid.ashx,Handler.ashx功能分别为:根据Guid取消正在上传的文件,生成Guid,根据Guid获取上传信息。
第一步:建立index.htm页面,这个上传页面,需要注意的就是需要一个隐藏的iframe,并且名字为form提交的目标。
<!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><title>ASP.NET Ajax文件上传进度条示例</title><meta name="author" content="李检全" /><link href="Styles/base.css" rel="stylesheet" type="text/css" /><script src="Scripts/jquery-1.4.2.min.js" type="text/javascript"></script><script src="Scripts/jquery-ui-1.8.2.custom.min.js" type="text/javascript"></script><script src="Scripts/ljq.lib.js" type="text/javascript"></script><script src="Scripts/Ajax/GuidGet.js" type="text/javascript"></script><script src="Scripts/Ajax/ajax-progress-upload.js" type="text/javascript"></script> </head> <body><div id="upload_demo"> <div class="title">ASP.NET Ajax 文件上传进度条示例</div> <form action="UploadHandler/Default.aspx" enctype="multipart/form-data" method="post" target="upload_hidden_iframe"><input id="guid" name="guid" value="" type="hidden" /><p>*本程序适合小文件上传,不超过80Mb</p><p>文件地址</p><input name="upload_file" type="file" /><br /><p>文件描述</p><textarea name="description_file"></textarea><br /><br /><input type="submit" value="上传文件" /> </form></div><div id="back_panel"></div><div id="upload_panel"> <div id="upload_title">文件上传</div> <div id="upload_content"> <ul> <li id="finished_percent">正在准备上传...</li> <li><div id="upload_bar"><div id="upload_progress"></div></div></li> <li id="upload_speed"></li> <li id="upload_costTime"></li> <li id="upload_fileSize"></li> <li id="upload_fileName"></li></ul> <div id="upload_detail"></div><div id="upload_choose"> <span id="upload_cancel">取消</span><span id="upload_submit">确定</span></div> </div></div><iframe name="upload_hidden_iframe" style="display:none;"></iframe> </body> </html>
第二步,创建GenerateGuid.ashx文件,作用就是生成唯一的Guid。
<%@ WebHandler Language="C#" Class="ProgressHandler.Handler" %>using System; using System.Web; using System.Xml.Linq;namespace ProgressHandler {public class Handler : IHttpHandler{ /// <summary> /// 获得上传文件的GUID /// </summary> /// <param name="context">当前请求实体</param> /// <creattime>2015-06-28</creattime> /// <author>FreshMan</author> public void ProcessRequest(HttpContext context) {context.Response.Charset = "utf-8";context.Response.ContentType = "application/xml";var guid = Guid.NewGuid().ToString();var doc = new XDocument();var root = new XElement("root"); var xGuid = new XElement("guid", guid);root.Add(xGuid);doc.Add(root);context.Response.Write(doc.ToString());context.Response.End(); }public bool IsReusable {get { return false; } } } } 第三步,创建Default.aspx文件,用于提交表单时上传文件。
using System;namespace UploadHandler {public partial class UploadHandlerDefault : System.Web.UI.Page{ protected void Page_Load(object sender, EventArgs e) {string guid = Request.Params["guid"];UploadUtil utilHelp = new UploadUtil(this, guid);utilHelp.Upload(); }} } 上传核心代码:
using System; using System.Web; using System.IO; using System.Configuration; using System.Web.UI; using System.Web.Caching; using System.Threading; public class UploadUtil {private Stream _reader;private FileStream _fStream;private const int Buffersize = 10000;private readonly string _filePath =new Page().Server.MapPath(ConfigurationManager.AppSettings["upload_folder"]);private readonly Page _page;private readonly string _guid;public UploadUtil(Page page, string guid){ _page = page; _guid = guid;}public void Upload(){ if (_page.Request.Files.Count > 0) {DoUpload(_page.Request.Files[0]); }}private void DoUpload(HttpPostedFile postedFile){ bool abort = false; string uploadFilePath = _filePath + DateTime.Now.ToFileTime()+"//"; if (!Directory.Exists(uploadFilePath)) {Directory.CreateDirectory(uploadFilePath); } string uploadFileName = postedFile.FileName; DownloadingFileInfo info = new DownloadingFileInfo(uploadFileName, postedFile.ContentLength, postedFile.ContentType); object fileObj = HttpContext.Current.Cache[_guid]; if (fileObj != null) {HttpContext.Current.Cache.Remove(_guid); } HttpContext.Current.Cache.Add(_guid, info, null, DateTime.Now.AddDays(1), TimeSpan.Zero, CacheItemPriority.AboveNormal, null); DateTime begin=DateTime.Now.ToLocalTime(); _fStream = new FileStream(uploadFilePath + uploadFileName, FileMode.Create); _reader = postedFile.InputStream; byte []buffer=new byte[Buffersize]; int len = _reader.Read(buffer,0,Buffersize);while (len > 0&&!abort) {_fStream.Write(buffer,0,len);DateTime end = DateTime.Now.ToLocalTime();info.CostTime = (long)(end - begin).TotalMilliseconds;info.FileFinished += len; //模拟延时用,实际应用的时候注销他Thread.Sleep(1000); HttpContext.Current.Cache[_guid] = info;abort=((DownloadingFileInfo)HttpContext.Current.Cache[_guid]).Abort;len = _reader.Read(buffer,0,Buffersize); } _reader.Close(); _fStream.Close(); if (abort) {if (File.Exists(uploadFilePath + uploadFileName)){ File.Delete(uploadFilePath + uploadFileName);} }} }
第四步,创建Handler.ashx文件,用于查看文件上传情况。
<%@ WebHandler Language="C#" Class="ProgressHandler.Handler" %>using System.Web; using System.Xml.Linq;namespace ProgressHandler {public class Handler : IHttpHandler{ /// <summary> /// 获得上传文件的进度 /// </summary> /// <param name="context">当前请求实体</param> /// <creattime>2015-06-28</creattime> /// <author>FreshMan</author> public void ProcessRequest(HttpContext context) {context.Response.ContentType = "application/xml";context.Response.Charset = "utf-8";var guid = context.Request.Form["guid"];var info = context.Cache[guid] as DownloadingFileInfo;var doc = new XDocument();var root = new XElement("root");if (info != null){ var fileName = new XElement("fileName", info.FileName); var fileFinished = new XElement("fileFinished", info.FileFinished); var fileSize = new XElement("fileSize", info.FileSize); var costTime = new XElement("costTime", info.CostTime); var fileState = new XElement("fileState", info.FileState); var speed = new XElement("speed", info.Speed); var percent = new XElement("percent", info.Percent); var abort = new XElement("abort", false); root.Add(fileName); root.Add(fileFinished); root.Add(fileSize); root.Add(costTime); root.Add(fileState); root.Add(speed); root.Add(percent); if (info.Abort) {abort.Value = info.Abort.ToString();context.Cache.Remove(guid); } if (info.FileState == "finished") {context.Cache.Remove(guid); }}else{ var none = new XElement("none", "no file"); root.Add(none);}doc.Add(root);context.Response.Write(doc.ToString());context.Response.End(); }public bool IsReusable {get { return false; } }} } 第五步,创建Abort.ashx文件,用于取消上传。
<%@ WebHandler Language="C#" Class="ProgressHandler.Abort" %> using System.Web; using System.Xml.Linq;namespace ProgressHandler {public class Abort : IHttpHandler{ /// <summary> /// 取消上传处理程序 /// </summary> /// <param name="context">当前请求实体</param> /// <creattime>2015-06-28</creattime> /// <author>FreshMan</author> public void ProcessRequest(HttpContext context) {context.Response.ContentType = "application/xml";context.Response.Charset = "utf-8";var guid = context.Request.Form["guid"];var abort = !string.IsNullOrEmpty(context.Request.Form["abort"]);var info = context.Cache[guid] as DownloadingFileInfo;if (info != null){ info.Abort = abort; context.Cache[guid] = info;}var doc = new XDocument();var root = new XElement("root");var flag = new XElement("flag", info == null ? "false" : "true");root.Add(flag);doc.Add(root);context.Response.Write(doc.ToString());context.Response.End(); }public bool IsReusable {get { return false; } } } } 好了,下面就是编写javascript脚本了,我引用了jquery这个框架,另外还用了ui框架。
核心代码是ajax-progress-upload.js文件,另外还有一个获取guid的文件。
$(document).ready(function () {var _guid_url = "ProgressHandler/GenerateGuid.ashx";var _progress_url = "ProgressHandler/Handler.ashx";var _abort_url = "ProgressHandler/Abort.ashx";var _target = "#guid";var _guid = "";var _cancel = false;var _timer;LJQ.setGuid(_target, _guid_url);$("#upload_panel").draggable({ handle: "#upload_title" });$("#upload_choose span").hover(function () { $(this).css({"color": "#f6af3a","border": "1px solid #e78f08" });}, function () { $(this).css({"color": "#1c94cd","border": "1px solid #ddd" });});$("#upload_cancel").click(function () { $.ajax({url: _abort_url,data: { guid: _guid, abort: true },dataType: "xml",type: "post",success: function () {$("#upload_panel").fadeOut("fast"); $("#back_panel").fadeOut(1000); window.clearInterval(_timer);} });});$("#upload_submit").click(function () { $("#upload_panel").fadeOut("fast"); $("#back_panel").fadeOut("1000");});$("form").submit(function () { _guid = $(_target).val(); if ($("input[name="upload_file"]").val() == "") {alert("未指定上传文件!");return false; } $("#upload_progress").css("width", "0%"); $("#finished_percent").html("准备上传..."); $("#upload_speed").html(""); $("#upload_fileName").html(""); $("#upload_fileSize").html(""); $("#upload_costTime").html(""); var _option = {url: _progress_url,data: { guid: _guid },dataType: "xml",type: "post",beforeSend: function () { $("#back_panel").fadeTo("fast", "0.5"); $("#upload_panel").fadeIn("1000");},success: function (response) {if ($(response).find("root abort").text() == "true") {$("#upload_panel").fadeOut("fast");$("#back_panel").fadeOut(1000);window.clearInterval(_timer); }else if ($(response).find("root none").text() == "no file") {} else {var _percent = ($(response).find("root percent").text() * 100);var _speed = $(response).find("root speed").text();var _fileSize = $(response).find("root fileSize").text();var _upload_costTime = $(response).find("root costTime").text();if (parseInt(_speed) < 1024) { _speed = LJQ.toFix(_speed) + "Kb";} else { _speed = LJQ.toFix(_speed / 1024) + "Mb";} if (parseInt(_fileSize) / 1024 < 1024) { _fileSize = LJQ.toFix(_fileSize / 1024) + "Kb";} else if (parseInt(_fileSize) / 1024 / 1024 < 1024) { _fileSize = LJQ.toFix(_fileSize / 1024 / 1024) + "Mb";} else { _fileSize = LJQ.toFix(_fileSize / 1024 / 1024 / 1024) + "Gb";} if (_upload_costTime < 1000) { _upload_costTime = _upload_costTime + "毫秒";} else if (_upload_costTime / 1000 < 60) { _upload_costTime = parseInt(_upload_costTime / 1000) + "秒" + _upload_costTime % 1000 + "毫秒";} else { _upload_costTime = parseInt(_upload_costTime / 1000 / 60) + "分" + parseInt((_upload_costTime % 60000) / 1000) + "秒" + _upload_costTime % 1000 + "毫秒";}$("#upload_progress").css("width", parseInt(_percent) + "%");$("#finished_percent").html("完成百分比:" + LJQ.toFix(_percent) + "%");$("#upload_speed").html("上传速度:" + _speed + "/sec");$("#upload_fileName").html("文件名称:" + $(response).find("root fileName").text());$("#upload_fileSize").html("文件大小:" + _fileSize);$("#upload_costTime").html("上传耗时:" + _upload_costTime);if (_percent >= 100) {window.clearInterval(_timer); $("#finished_percent").html("<span style="color:green;">文件上传完成</span>");}if (_cancel) { window.clearInterval(_timer);} } },error: function () { } };_timer = window.setInterval(function () { $.ajax(_option); }, 1000); });}); 以上为代码的主要部分。asp.net单文件带进度条上传,不属于任务控件,也不是flash类型的上传,完全是asp.net、js、css实现上传。源码为开发测试版,需要使用的亲需要注意修改配置文件。
项目源码下载请点击这里:http://xiazai.jb51.net/201509/yuanma/asp_net_progressbar(jb51.net).rar