asp.net单文件带进度条上传的解决方案

Z时代
2024-01-10
分类：综合

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); 
 }); 
});