private async void RetrieveVideoSize(YouTubeVideo ytv) { cbxFormat.IsEnabled = false; cbxResolution.IsEnabled = false; lblVideoSize.Content = "Getting size..."; try { YouTubeVideo.DownloadInfo dlInfo = GetDownloadInfo(ytv, cbxFormat.SelectedValue as string, cbxResolution.SelectedValue as string); FileSize sz = await YouTubeVideo.GetVideoSizeAsync(dlInfo); lblVideoSize.Content = sz.ToString(); } catch { lblVideoSize.Content = "Unable to get size."; } finally { cbxFormat.IsEnabled = true; cbxResolution.IsEnabled = true; } }