private void Create_Click(object sender, RoutedEventArgs e) { User user = new User() { Name = Name.Text, Password = Password.Text }; if (Name.Text.Count() == 0) { MessageBox.Show("user Name cannot be blank"); return; } if (Password.Text.Count() == 0) { MessageBox.Show("password cannot be blank"); return; } User user1 = users.Where(u => u.Name == Name.Text).SingleOrDefault(); if (user1 != null) { MessageBox.Show("User already exists"); return; } else { user.Level = 2; vm.Saveuser(user); } users.Add(user); UserInfo.Visibility = Visibility.Hidden; PassInfo.Visibility = Visibility.Hidden; Create.Visibility = Visibility.Hidden; Name.Text = ""; Password.Text = ""; CreateUser.Focus(); }