C# 中限制下載速度

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/// <summary> /// 速度限制、資源佔用小 /// </summary> /// <param name="_Request">Page.Request對象</param> /// <param name="_Response">Page.Response對象</param> /// <param name="_fileName">下載檔案名稱</param> /// <param name="_fullPath">帶檔案名稱下載路徑</param> /// <param name="_speed">每秒允許下載的位元組數</param> /// <returns>返回是否成功</returns> public static bool ResponseFile(HttpRequest _Request, HttpResponse _Response, string _fileName, string _fullPath, long _speed) { try { FileStream myFile = new FileStream(_fullPath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite); BinaryReader br = new BinaryReader(myFile); try { _Response.AddHeader("Accept-Ranges", "bytes"); _Response.Buffer = false; long fileLength = myFile.Length; long startBytes = 0; int pack = 10240; //int sleep = 200; int sleep = (int)Math.Floor((double)(1000 * pack / _speed)) + 1; if (_Request.Headers["Range"] != null) { _Response.StatusCode = 206; string[] range = _Request.Headers["Range"].Split(new char[] { ‘=‘, ‘-‘ }); startBytes = Convert.ToInt64(range[1]); } _Response.AddHeader("Content-Length", (fileLength - startBytes).ToString()); if (startBytes != 0) { _Response.AddHeader("Content-Range", string.Format(" bytes {0}-{1}/{2}", startBytes, fileLength - 1, fileLength)); } _Response.AddHeader("Connection", "Keep-Alive"); _Response.ContentType = "application/octet-stream"; _Response.AddHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(_fileName, System.Text.Encoding.UTF8)); br.BaseStream.Seek(startBytes, SeekOrigin.Begin); int maxCount = (int)Math.Floor((double)((fileLength - startBytes) / pack)) + 1; for (int i = 0; i < maxCount; i++) { if (_Response.IsClientConnected) { _Response.BinaryWrite(br.ReadBytes(pack)); Thread.Sleep(sleep); } else { i = maxCount; } } } catch { return false; } finally { br.Close(); myFile.Close(); } } catch { return false; } return true; }

C# 中限制下載速度