#region 从服务器下载文件    /// <summary>    /// 从服务器下载文件    /// </summary>    /// <param name="_Request"></param>    /// <param name="_Response"></param>    /// <param name="_fileName">文件名称</param>    /// <param name="_fullPath">文件完整路径</param>    /// <param name="_speed">速度</param>    /// <returns></returns>    public 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; //10K bytes                //int sleep = 200;   //每秒5次   即5*10K bytes每秒                int sleep = (int)Math.Floor((decimal)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.Charset = "UTF-8";                _Response.ContentEncoding = Encoding.GetEncoding("UTF-8");                _Response.AddHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(_fileName, System.Text.Encoding.UTF8));                br.BaseStream.Seek(startBytes, SeekOrigin.Begin);                int maxCount = (int)Math.Floor((decimal)(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;                    }                }                _Response.End();            }            catch            {                return false;            }            finally            {                br.Close();                myFile.Close();                //下载后后删除路径              /*                if (File.Exists(_fullPath))                {                    File.Delete(_fullPath);                }              */            }        }        catch        {            return false;        }        return true;    }    #endregion