public byte[] DownLoadMsg(LogRetrieveForDto sMsg)
    {
        string fullPath = Path.Combine(Path.GetTempPath(), "0000-0000-0000");
        Stream str = GetDownloadStream(sMsg, fullPath);
        var bytes = new byte[str.Length];
        try
        {
            str.Read(bytes, 0, bytes.Length);
            // 设置当前流的位置为流的开始 
            str.Seek(0, SeekOrigin.Begin);
            return bytes;
        }
        catch (Exception e)
        {
            logger.Error("Log Scrub : read file error.", e);
            throw;
        }
        finally
        {
            str.Close();
            str.Dispose();
            File.Delete(fullPath);
        }
    }

  export_raw(name = '', data) {
      let eleLink = document.createElement('a');
      eleLink.style.display = 'none';
      eleLink.download =name?name: 'download.xls';
      data = "data:;base64," + data;
      if (window.navigator.msSaveOrOpenBlob) {// if browser is IE              
          let blob = this.dataURLtoBlob(data); 
          navigator.msSaveOrOpenBlob(blob, 'download.xls');
      } else {
          eleLink.href = data;
          document.body.appendChild(eleLink);
          eleLink.click();
          document.body.removeChild(eleLink);

      }

  }

  .then(response => response.blob())
        .then(blob => {
            var url = window.URL.createObjectURL(blob);
            var a = document.createElement('a');
            a.href = url;
            a.download = "filename.xlsx";
            a.click();                    
        });