c# - HttpWebRequest.GetResponse : "The underlying connection was closed: An unexpected error occurred on a receive."

Question

我编写了一个 C# Windows 服务(.NET Framework 3.5、C# 3.0)，它将文件和 HTML 表单信息发布到远程服务器，然后将 XML 服务器响应存储在数据库中。这是相关代码的主要部分:

    HttpWebRequest request = WebRequest.Create(postUrl) as HttpWebRequest;

    request.ProtocolVersion = HttpVersion.Version10;
    request.KeepAlive = false;
    request.Timeout = 600000;
    request.ReadWriteTimeout = 600000;
    request.Method = "POST";
    request.ContentType = contentType;
    request.UserAgent = userAgent;
    request.CookieContainer = new CookieContainer();
    request.ContentLength = formData.Length;

    using (Stream requestStream = request.GetRequestStream())
    {
        // Push it out there
        requestStream.Write(formData, 0, formData.Length);
        requestStream.Close();
    }

    return request.GetResponse() as HttpWebResponse;

我的服务适用于所有小文件，但当我尝试发送较大文件 (8-9 MB) 时出现以下错误。

    The underlying connection was closed: An unexpected error occurred on a receive.

我使用 Fiddler 查看了传出请求，并能够收集到以下信息:

    HTTP/1.1 504 Fiddler - Receive Failure
    Content-Type: text/html
    Connection: close
    Timestamp: 12:25:04.067

    ReadResponse() failed: The server did not return a response for this request.

失败发生在我调用 request.GetResponse() 后约 7 分钟。有什么办法可以确定是谁关闭了连接？还有什么我应该尝试解决这个问题的吗？提前致谢!

Answer 1

既然你提到它适用于小文件，而不是更大的文件，我建议检查服务器上的最大文件上传大小。我相信默认值是 4mb。 http://support.microsoft.com/kb/295626

编辑:注意到上面的链接有点过时了。这是 iis7 的一个:http://www.cyprich.com/2008/06/19/fixing-file-upload-size-limit-in-iis-7/