private ResponseFile DownloadFile(RequestFile request)
        {
            ResponseFile result = new ResponseFile();

            FileStream stream = this.GetFileStream(Path.GetFullPath(request.FileName));
            stream.Seek(request.byteStart, SeekOrigin.Begin);
            result.FileName = request.FileName;
            result.Length = stream.Length;
            result.FileByteStream = stream;
            return result;

        }
 public ResponseFile Download(RequestFile request)
 {
     var tsk = Task.Run(async () => await _serviceExecutor.Execute(s => s.WcfDownloadFile(request)));
     return (ResponseFile)tsk.Result;
 }
 public async Task<ResponseFile> StartDownloadFile(RequestFile request)
 {
     return await Task.Run(() => DownloadFile(request));
 }
 public async Task<ResponseFile> WcfDownloadFile(RequestFile request)
 {
     return await _transferService.StartDownloadFile(request);
 }