BaconographyW8.View.FileOpenPickerView.pickerSelectionChanged C# (CSharp) Method

        private async void pickerSelectionChanged(PickerFileMessage obj)
        {
            if (obj.Selected)
            {
                Uri uri = new Uri(obj.TargetUrl);
                string filename = Path.GetFileName(uri.LocalPath);

                var file = await ApplicationData.Current.TemporaryFolder.CreateFileAsync(filename, CreationCollisionOption.ReplaceExisting);
                var downloader = new BackgroundDownloader();
                var download = downloader.CreateDownload(
                    uri,
                    file);

                var res = await download.StartAsync();

                _fileOpenPickerUI.AddFile(obj.TargetUrl, file);
            }
            else if (_fileOpenPickerUI.ContainsFile(obj.TargetUrl))
            {
                _fileOpenPickerUI.RemoveFile(obj.TargetUrl);
            }

        }