The following AJAX File Upload jQuery Tutorial covers how to upload files asynchronously using jQuery Framework.

Generic Handler: AjaxFileUploader.ashx

1. public class AjaxFileUploader : IHttpHandler
2. {
3. public void ProcessRequest(HttpContext context)
4. {
5.     if (context.Request.Files.Count > 0)
6.     {
7.         string path = context.Server.MapPath("~/Files");
8.         if (!Directory.Exists(path))
9.             Directory.CreateDirectory(path);
10.         var file = context.Request.Files[0];
11.         string fileName;
12.         if (HttpContext.Current.Request.Browser.Browser.ToUpper() == "IE")
13.         {
14.             string[] files = file.FileName.Split(new char[] { '\\' });
15.             fileName = files[files.Length - 1];
16.         }
17.         else
18.         {
19.             fileName = file.FileName;
20.         }
21.         string strFileName = fileName;
22.         fileName = Path.Combine(path, fileName);
23.         file.SaveAs(fileName);
24.         string msg = "{";
25.         msg += string.Format("error:'{0}',\n", string.Empty);
26.         msg += string.Format("msg:'{0}',\n", strFileName);
27.         msg += string.Format("path:'{0}'", path.Replace("\\", "?"));
28.         msg += "}";
29.         context.Response.Write(msg);
30.     }
31. }
32. public bool IsReusable
33. {
34.     get
35.     {
36.         return true;
37.     }
38. }
39. }

HTML:

1. <div class="resumeUpload">
2.     <input type="file" id="fileToUpload" name="fileToUpload" onchange="ajaxFileUpload();" />
3.     <div class="fileBtn">
4.         <span>File</span>
5.         <input id="fileUploadBox" disabled="disabled" value="@GetDictionary("No files selected")" />
6.     </div>
7. </div>