[搜片神器]BT种子下载超时很多的问题分析

继续接着第一篇写:使用C#实现DHT磁力搜索的BT种子后端管理程序+数据库设计（开源）[搜片神器]

谢谢园子朋友的支持,已经找到个VPS进行测试,国外的服务器: h31bt.org 大家可以给提点意见...

开源地址:https://github.com/h31h31/H31DHTMgr

程序下载:H31DHT下载

下载种子文件的时候失败很多,增加调试信息总是返回很多:Timeouts are not supported on this stream.

The remote server returned an error: (404) Not Found.

The operation has timed out.

附上之前的代码:

        private int DownLoadFileToSaveFile(string strURL, string fileName)
        {
            Int32 ticktime1 = System.Environment.TickCount;
            try
            {
                Int32 ticktime2 = 0;
                byte[] buffer = new byte[4096];

                WebRequest wr = WebRequest.Create(strURL);
                wr.ContentType = "application/x-bittorrent";
                wr.Timeout = 300;
                WebResponse response = wr.GetResponse();
                int readsize = 0;
                {
                    bool gzip = response.Headers["Content-Encoding"] == "gzip";
                    Stream responseStream = gzip ? new GZipStream(response.GetResponseStream(), CompressionMode.Decompress) : response.GetResponseStream();

                    using (MemoryStream memoryStream = new MemoryStream())
                    {
                        responseStream.ReadTimeout = 1000;
                        int count = 0;
                        do
                        {
                            count = responseStream.Read(buffer, 0, buffer.Length);
                            memoryStream.Write(buffer, 0, count);
                            readsize += count;
                            Thread.Sleep(1);
                        } while (count != 0);
                        ticktime2 = System.Environment.TickCount;

                        byte[] result = memoryStream.ToArray();
                        Thread.Sleep(10);
                        using (BinaryWriter writer = new BinaryWriter(new FileStream(fileName, FileMode.Create)))
                        {
                            writer.Write(result);
                        }
                    }
                    Int32 ticktime3 = System.Environment.TickCount;
                    //H31Debug.PrintLn("下载成功" + strURL + ":" + readsize.ToString() + ":" + (ticktime2 - ticktime1).ToString() + "-" + (ticktime3 - ticktime2).ToString());
                }
                return 1;
            }
            catch (Exception e)
            {
                Int32 ticktime3 = System.Environment.TickCount;
                //H31Debug.PrintLn("下载失败" + strURL + ":" +  (ticktime3 - ticktime1).ToString());
                return -2;
            }
        }

测试在国内服务器上情况很少时间,一放到国外服务器上就出现此问题,网上搜索资料最终显示是

参考1:http://stackoverflow.com/questions/9791423/httpwebresponse-readtimeout-timeouts-not-supported

经过代码分析,原来Stream responseStream里面使用的TIMEOUT参数设置.

                    Stream responseStream = gzip ? new GZipStream(response.GetResponseStream(), CompressionMode.Decompress) : response.GetResponseStream();

                    using (MemoryStream memoryStream = new MemoryStream())
                    {
                        responseStream.ReadTimeout = 1000;
                        int count = 0;
                        do
                        {
                            count = responseStream.Read(buffer, 0, buffer.Length);
                            memoryStream.Write(buffer, 0, count);
                            readsize += count;
                            Thread.Sleep(1);
                        } while (count != 0);
                        ticktime2 = System.Environment.TickCount;

                        byte[] result = memoryStream.ToArray();
                        Thread.Sleep(10);
                        using (BinaryWriter writer = new BinaryWriter(new FileStream(fileName, FileMode.Create)))
                        {
                            writer.Write(result);
                        }
                    }

然后为了防止程序界面卡住,错误的增加了Thread.Sleep(1);其它问题可能就出现在此地方,由于设置超时,然后数据流就被超时退出,从而被系统认为Stream没有注销导致异常,从而显示Timeouts are not supported on this stream.

修改后的代码为:

        private int DownLoadFileToSaveFile(string strURL, string fileName,int timeout1)
        {
            Int32 ticktime1 = System.Environment.TickCount;
            try
            {
                Int32 ticktime2 = 0;
                byte[] buffer = new byte[4096];

                WebRequest wr = WebRequest.Create(strURL);
                wr.ContentType = "application/x-bittorrent";
                wr.Timeout = timeout1;
                WebResponse response = wr.GetResponse();
                int readsize = 0;
                {
                    bool gzip = response.Headers["Content-Encoding"] == "gzip";
                    Stream responseStream = gzip ? new GZipStream(response.GetResponseStream(), CompressionMode.Decompress) : response.GetResponseStream();

                    using (MemoryStream memoryStream = new MemoryStream())
                    {
                        int count = 0;
                        do
                        {
                            count = responseStream.Read(buffer, 0, buffer.Length);
                            memoryStream.Write(buffer, 0, count);
                            readsize += count;
                        } while (count != 0);
                        ticktime2 = System.Environment.TickCount;

                        byte[] result = memoryStream.ToArray();
                        Thread.Sleep(10);
                        using (BinaryWriter writer = new BinaryWriter(new FileStream(fileName, FileMode.Create)))
                        {
                            writer.Write(result);
                        }
                    }
                    Int32 ticktime3 = System.Environment.TickCount;
                    //H31Debug.PrintLn("下载成功" + strURL + ":" + readsize.ToString() + ":" + (ticktime2 - ticktime1).ToString() + "-" + (ticktime3 - ticktime2).ToString());
                }
                return 1;
            }
            catch (WebException e)
            {
                Int32 ticktime3 = System.Environment.TickCount;
                if (e.Status == WebExceptionStatus.Timeout)//文件超时
                {
                    return -2;
                }
                else if (e.Status == WebExceptionStatus.ProtocolError)//文件不存在
                {
                    return -3;
                }
                else
                {
                    H31Debug.PrintLn("下载失败" + strURL + ":" + (ticktime3 - ticktime1).ToString() + e.Status.ToString() + e.Message);
                    return -4;
                }
            }
        }