private async void Favorite(object obj) { var client = new TwitterClient(accessToken); HttpResponseMessage res; try { if (state == States.Retweeted) { res = await client.ChangeFavorite(source); } else { res = await client.ChangeFavorite(tweet); } if (!res.IsSuccessStatusCode) { throw new Exception(res.ReasonPhrase); } else { if ((bool)tweet.favorited) { favoriteImageUrl = "/Assets/TwitterIcons/favorite.png"; tweet.favorited = false; } else { favoriteImageUrl = "/Assets/TwitterIcons/favorite_on.png"; tweet.favorited = true; } } } catch (Exception ex) { //throw new Exception("おや? なにかがおかしいようです。", ex); var message = new MessageDialog(ex.Message, "おや? なにかがおかしいようです。"); await message.ShowAsync(); } }