private void DeleteSelectedUser(User selectedUser) { if (selectedUser != null) { var response = MessageBox.Show("Do you really want to delete user " + selectedUser.ToString(), "Deleting...", MessageBoxButton.YesNo, MessageBoxImage.Exclamation); if (response == MessageBoxResult.Yes) { OLModel.Helpers.AdminLog("User {0} was deleted.", selectedUser); Model.Instance.Users.Remove(selectedUser); } } }