如果直接运行官方所给的示例是能够成功运行的。但如果想运行在“无dll”文件的环境里面还需要注意以下几点：
1、页面session和flash session是不相同的，所以在操作的时候还要把Global.asax里面的内容放到工程下。因为这个示例是将上传的图片存放到内存中的，所以每次都要从session中取信息，如果不在request开始前进行操作，页面跟flash取到的是两个不同的会话，这就会成就图片上传成功，但看不到上传的内容。
void Application_BeginRequest(object sender, EventArgs e)
{
/* Fix for the Flash Player Cookie bug in Non-IE browsers.
* Since Flash Player always sends the IE cookies even in FireFox
* we have to bypass the cookies by sending the values as part of the POST or GET
* and overwrite the cookies with the passed in values.
*
* The theory is that at this point (BeginRequest) the cookies have not been read by
* the Session and Authentication logic and if we update the cookies here we’ll get our
* Session and Authentication restored correctly
*/
try
{
string session_param_name = "ASPSESSID";
string session_cookie_name = "ASP.NET_SESSIONID";
if (HttpContext.Current.Request.Form[session_param_name] != null)
{
UpdateCookie(session_cookie_name, HttpContext.Current.Request.Form[session_param_name]);
}
else if (HttpContext.Current.Request.QueryString[session_param_name] != null)
{
UpdateCookie(session_cookie_name, HttpContext.Current.Request.QueryString[session_param_name]);
}
}
catch (Exception)
{
Response.StatusCode = 500;
Response.Write("Error Initializing Session");
}
try
{
string auth_param_name = "AUTHID";
string auth_cookie_name = FormsAuthentication.FormsCookieName;
if (HttpContext.Current.Request.Form[auth_param_name] != null)
{
UpdateCookie(auth_cookie_name, HttpContext.Current.Request.Form[auth_param_name]);
}
else if (HttpContext.Current.Request.QueryString[auth_param_name] != null)
{
UpdateCookie(auth_cookie_name, HttpContext.Current.Request.QueryString[auth_param_name]);
}
}
catch (Exception)
{
Response.StatusCode = 500;
Response.Write("Error Initializing Forms Authentication");
}
}
void UpdateCookie(string cookie_name, string cookie_value)
{
HttpCookie cookie = HttpContext.Current.Request.Cookies.Get(cookie_name);
if (cookie == null)
{
cookie = new HttpCookie(cookie_name);
HttpContext.Current.Request.Cookies.Add(cookie);
}
cookie.Value = cookie_value;
HttpContext.Current.Request.Cookies.Set(cookie);
}
当然，另外还需要通过ASPSESSID参数将sessionid传递给服务端
post_params : {
"ASPSESSID" : "<%=Session.SessionID %>"
},
2、如果将Thumbnail.cs的内容改成Thumbnail.txt然后分别引入到upload.aspx和thumbnail.aspx中，也会造成问题，因为两个页面对应是并不是同一个类，所以会造成转换失败同样取不到所上传的图片。解决方法可以是将upload.aspx和thumbnail.aspx两个页面的内容合并，也可以是使用App_Code。
3、将文件保存目录中，通过Directory.Exists来判断目录是否存在，通过Directory.CreateDirectory来创建目录
HttpPostedFile file_upload = Request.Files["Filedata"];
display_file_name = file_upload.FileName;
file_size = file_upload.ContentLength;
string dir = DateTime.Now.ToString("yyyyMMdd");
string filename = DateTime.Now.ToString("yyyyMMddHHmmssfff");
string serverpath = Server.MapPath("file/") + dir + "/";
if (!Directory.Exists(serverpath))
{
DirectoryInfo dirinfo = Directory.CreateDirectory(serverpath);
}
string ext = file_upload.FileName.Substring(file_upload.FileName.LastIndexOf("."));
physical_file_name = filename + ext;
physical_file_path = serverpath + filename + ext;
file_upload.SaveAs(physical_file_path);
4、在用input file模拟时，还要记得在form的提交方式
<form id="form1" action="upload.aspx" method="post" enctype="multipart/form-data">
5、补充一下html头部的信息写法
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<meta name="author" content="tohours.com" />
<title>后台管理登录</title>
</head>
<body>
</body>
</html>
