private void SignUpClicked(object sender, RoutedEventArgs e) { if (FirstNameTextBox.Text != "" || LastNameTextBox.Text != "" || EmailTextBox.Text != "" || MobileNumberTextBox.Text != "" || AgeTextBox.Text != "" || GenderTextBox.Text != "" || PasswordTextBox.Password != "" || ConfirmPasswordTextBox.Password != "") { if (notContainsAlphabet(AgeTextBox.Text)) { if (MobileNumberTextBox.Text.Length == 11 && notContainsAlphabet(MobileNumberTextBox.Text)) { if (PasswordTextBox.Password == ConfirmPasswordTextBox.Password) { string clause = "WHERE email = '" + EmailTextBox.Text + "';"; DataTable dt = DatabaseHandler.Select("Users", clause); if (dt.Rows.Count == 0) { if (new User().addUser( FirstNameTextBox.Text, LastNameTextBox.Text, EmailTextBox.Text, MobileNumberTextBox.Text, GenderTextBox.Text, int.Parse(AgeTextBox.Text), PasswordTextBox.Password)) { DataTable dt2 = DatabaseHandler.Select("Users", new string[] { "userID" }, $"WHERE email = '{EmailTextBox.Text}';"); signUpUserID = int.Parse(dt2.Rows[0][0].ToString()); signUpUser = true; Login.loginUser = false; MessageBox.Show("Signed up Successfully", "Done!", MessageBoxButton.OK); NavigationService.Navigate(new Uri("Home.xaml", UriKind.RelativeOrAbsolute)); } else { MessageBox.Show("An unknown error occured /nPlease try again", "Error", MessageBoxButton.OK); } } else { MessageBox.Show("This email already exists, please login", "Error", MessageBoxButton.OK); } } else { MessageBox.Show("The passwords don't match", "Error", MessageBoxButton.OK); } } else { MessageBox.Show("Please enter your mobile number correctly", "Error", MessageBoxButton.OK); } } else { MessageBox.Show("Please enter your age correctly", "Error", MessageBoxButton.OK); } } else { MessageBox.Show("Please make sure that you entered all the fields correctly", "Error", MessageBoxButton.OK); } }