UPDATED
看帖子#3 https://stackoverflow.com/questions/1060966/big-files-uploading-webexception-the-connection-was-closed-unexpectedly/1066265#1066265 below.
需要自动将文件上传到网络（无需浏览器）。主持人 -（如果这确实重要的话）。在文档中没有找到具体的api，所以首先我在Firebug中嗅探了浏览器请求，如下所示：
Params : do
Value : verify
POST /upload.php?do=verify HTTP/1.1
Host: webfile.ukrwest.net
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.2; ru; rv:1.9.0.8) Gecko/2009032609 Firefox/3.0.8 (.NET CLR 4.0.20506)
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: ru,en-us;q=0.7,en;q=0.3
Accept-Encoding: gzip,deflate
Accept-Charset: windows-1251,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Referer: http://filehoster.awardspace.com/index.php
Content-Type: multipart/form-data; boundary=---------------------------27368237179714
Content-Length: 445
-----------------------------27368237179714
Content-Disposition: form-data; name="upfile"; filename="Test.file"
Content-Type: application/octet-stream
12345678901011121314151617sample text
-----------------------------27368237179714
Content-Disposition: form-data; name="descr"
-----------------------------27368237179714
Content-Disposition: form-data; name="pprotect"
-----------------------------27368237179714--
在这里我们可以看到参数、标题、内容类型和信息块（1 - 文件名和类型，2 - 文件内容，3 - 附加参数 - 描述和密码，不一定适用）。
因此，我创建了一个逐步模拟此类行为的类：在 url 上使用 HttpWebRequest，将所需的参数应用于请求，使用 StringBuilder 形成请求字符串并将其转换为字节数组，使用 FileStream 读取文件，将所有内容放入MemoryStream，然后将其写入请求（代码的主要部分取自 CodeProject 上的一篇文章，其中将文件上传到 Rapidshare 主机）。
整洁，但是...它似乎不起作用:(。结果它返回初始上传页面，而不是带有我可以解析并呈现给用户的链接的结果页面...
以下是 Uploader 类的主要方法：
// Step 1 - request creation
private HttpWebRequest GetWebrequest(string boundary)
{
Uri uri = new Uri("http://filehoster.awardspace.com/index.php?do=verify");
System.Net.HttpWebRequest httpWebRequest = (System.Net.HttpWebRequest)System.Net.WebRequest.Create(uri);
httpWebRequest.CookieContainer = _cookies;
httpWebRequest.ContentType = "multipart/form-data; boundary=" + boundary;
httpWebRequest.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.2; ru; rv:1.9.0.8) Gecko/2009032609 Firefox/3.0.8 (.NET CLR 4.0.20506)";
httpWebRequest.Referer = "http://filehoster.awardspace.com/index.php";
httpWebRequest.Method = "POST";
httpWebRequest.KeepAlive = true;
httpWebRequest.Timeout = -1;
//httpWebRequest.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8";
httpWebRequest.Headers.Add("Accept-Charset", "windows-1251,utf-8;q=0.7,*;q=0.7");
httpWebRequest.Headers.Add("Accept-Encoding", "gzip,deflate");
httpWebRequest.Headers.Add("Accept-Language", "ru,en-us;q=0.7,en;q=0.3");
//httpWebRequest.AllowAutoRedirect = true;
//httpWebRequest.ProtocolVersion = new Version(1,1);
//httpWebRequest.SendChunked = true;
//httpWebRequest.Headers.Add("Cache-Control", "no-cache");
//httpWebRequest.ServicePoint.Expect100Continue = false;
return httpWebRequest;
}
// Step 2 - first message part (before file contents)
private string GetRequestMessage(string boundary, string FName, string description, string password)
{
System.Text.StringBuilder stringBuilder = new StringBuilder();
stringBuilder.Append("--");
stringBuilder.Append(boundary);
stringBuilder.Append("\r\n");
stringBuilder.Append("Content-Disposition: form-data; name=\"");
stringBuilder.Append("upfile");
stringBuilder.Append("\"; filename=\"");
stringBuilder.Append(FName);
stringBuilder.Append("\"");
stringBuilder.Append("\r\n");
stringBuilder.Append("Content-Type: application/octet-stream");
stringBuilder.Append("\r\n");
return stringBuilder.ToString();
}
// Step 4 - additional request parameters. Step 3 - reading file is in method below
private string GetRequestMessageEnd(string boundary)
{
System.Text.StringBuilder stringBuilder = new StringBuilder();
stringBuilder.Append(boundary);
stringBuilder.Append("\r\n");
stringBuilder.Append("Content-Disposition: form-data; name=\"descr\"");
stringBuilder.Append("\r\n");
stringBuilder.Append("\r\n");
stringBuilder.Append("Default description");
stringBuilder.Append("\r\n");
stringBuilder.Append(boundary);
stringBuilder.Append("\r\n");
stringBuilder.Append("Content-Disposition: form-data; name=\"pprotect\"");
stringBuilder.Append("\r\n");
stringBuilder.Append("\r\n");
stringBuilder.Append("");
stringBuilder.Append("\r\n");
stringBuilder.Append(boundary);
stringBuilder.Append("--");
//stringBuilder.Append("\r\n");
//stringBuilder.Append(boundary);
//stringBuilder.Append("\r\n");
return stringBuilder.ToString();
}
// Main method
public string ProcessUpload(string FilePath, string description, string password)
{
// Chosen file information
FileSystemInfo _file = new FileInfo(FilePath);
// Random boundary generation
DateTime dateTime2 = DateTime.Now;
long l2 = dateTime2.Ticks;
string _generatedBoundary = "----------" + l2.ToString("x");
// Web request creation
System.Net.HttpWebRequest httpWebRequest = GetWebrequest(_generatedBoundary);
// Main app block - form and send request
using (System.IO.FileStream fileStream = new FileStream(_file.FullName, FileMode.Open, FileAccess.Read, FileShare.Read))
{
byte[] bArr1 = Encoding.ASCII.GetBytes("\r\n--" + _generatedBoundary + "\r\n");
// Generating pre-content post message
string firstPostMessagePart = GetRequestMessage(_generatedBoundary, _file.Name, description, password);
// Writing first part of request
byte[] bArr2 = Encoding.UTF8.GetBytes(firstPostMessagePart);
Stream memStream = new MemoryStream();
memStream.Write(bArr1, 0, bArr1.Length);
memStream.Write(bArr2, 0, bArr2.Length);
// Writing file
byte[] buffer = new byte[1024];
int bytesRead = 0;
while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
{
memStream.Write(buffer, 0, bytesRead);
}
// Generating end of a post message
string secondPostMessagePart = GetRequestMessageEnd(_generatedBoundary);
byte[] bArr3 = Encoding.UTF8.GetBytes(secondPostMessagePart);
memStream.Write(bArr3, 0, bArr3.Length);
// Preparing to send
httpWebRequest.ContentLength = memStream.Length;
fileStream.Close();
Stream requestStream = httpWebRequest.GetRequestStream();
memStream.Position = 0;
byte[] tempBuffer = new byte[memStream.Length];
memStream.Read(tempBuffer, 0, tempBuffer.Length);
memStream.Close();
// Sending request
requestStream.Write(tempBuffer, 0, tempBuffer.Length);
requestStream.Close();
}
// Delay (?)
System.Threading.Thread.Sleep(5000);
// Getting response
string strResponse = "";
using (Stream stream = httpWebRequest.GetResponse().GetResponseStream())
using (StreamReader streamReader = new StreamReader(stream/*, Encoding.GetEncoding(1251)*/))
{
strResponse = streamReader.ReadToEnd();
}
return strResponse;
}
使用 ProtocolVersion（1.0、1.1）、AllowAutoRedirect（真/假），甚至已知的 ServicePoint.Expect100Continue（假）也没有解决问题。即使在获得响应之前有 5 秒的超时（认为在大文件的情况下它不会上传得那么快）也没有帮助。
故意选择内容类型“octet-stream”来上传任何文件（可以对最流行的 jpg/zip/rar/doc 等使用一些开关，但这似乎是通用的）。边界是从计时器滴答声中随机生成的，没什么大不了的。还有什么？ :/
我可以放弃并忘记这个，但我觉得我已经很接近解决问题了then忘记它吧：P。
如果您需要运行和调试整个应用程序 - 这里是（70kb，压缩的 C# 2.0 VS2k8 解决方案，无广告，无病毒）：
@Mediafire http://www.mediafire.com/download.php?no1tlmln3yy
@FileQube http://www.fileqube.com/file/RZPUGRwxE203936
@FileDropper http://www.filedropper.com/uploader
