private async void button_Click(object sender, RoutedEventArgs e) { Button obj = (Button)sender; if ((string)(obj.CommandParameter) == "1") { await WeBallAPI.joinMatch(match.teams[0]._id); if (WeBallAPI.Success == false) { return; } } else { await WeBallAPI.joinMatch(match.teams[1]._id); if (WeBallAPI.Success == false) { return; } } if (WeBallAPI.Success) { NavigationService.Navigate(new Uri("/MatchTimingPage.xaml?five=" + JsonConvert.SerializeObject(five), UriKind.Relative)); setPopup("Succes!"); } else { setPopup("Erreur"); } }