NaturalGroundingPlayer.EditVideoWindow.DownloadUrlText_LostFocus C# (CSharp) Méthode

        private async void DownloadUrlText_LostFocus(object sender, RoutedEventArgs e) {
            isUrlValid = false;
            ErrorText.Text = "";
            if (video.DownloadUrl.Length > 0) {
                try {
                    var VTask = DownloadBusiness.GetDownloadUrlsAsync(video.DownloadUrl);
                    var VideoList = await VTask;
                    VideoInfo FirstVid = VideoList.FirstOrDefault();
                    if (FirstVid != null) {
                        video.DownloadName = FirstVid.Title;
                        isUrlValid = true;
                    }
                } catch { }
                if (!isUrlValid)
                    ErrorText.Text = "Please enter a valid URL";
            }
        }