private async void OpenItem(File file)
        {
            if (file == null)
            {
                return;
            }

            //UploadFileName = file.filename;
            await TryAsyncApi("Open " + file.filename,
                              async() => GistContents = await _gistClient.DownloadRawText(new Uri(file.raw_url)));
        }
 public async Task <string> GetFileContentByUri(string rawUri)
 {
     return(await client.DownloadRawText(new Uri(rawUri)));
 }