private void btnCosts_Click(object sender, RoutedEventArgs e)
        {
            UserCostsWindow UserCostsWindow = new UserCostsWindow();

            UserCostsWindow.Show();
            this.Hide();
        }
        private void Back_to_Costs(object sender, RoutedEventArgs e)
        {
            UserCostsWindow userCostsWindow = new UserCostsWindow();

            userCostsWindow.Show();
            Hide();
        }
        private void Button_Auth_Click(object sender, RoutedEventArgs e)
        {
            string login = textBoxLogin.Text.Trim();
            string pass  = passBox.Password.Trim();

            if (login.Length < 5)
            {
                textBoxLogin.ToolTip     = "Это поле заполнено некоректно";
                textBoxLogin.BorderBrush = Brushes.DarkRed;
            }

            else if (pass.Length < 5)
            {
                passBox.ToolTip     = "Это поле заполнено некоректно";
                passBox.BorderBrush = Brushes.DarkRed;
            }
            else
            {
                textBoxLogin.ToolTip    = null;
                textBoxLogin.Background = Brushes.Transparent;
                passBox.ToolTip         = null;
                passBox.Background      = Brushes.Transparent;

                User authUser = null;
                using (ApplicationContext db = new ApplicationContext())
                {
                    authUser = db.Users.Where(b => b.Login == login && b.Pass == pass).FirstOrDefault();
                }

                if (authUser != null)
                {
                    MessageBox.Show("Авторизация прошла успешно!");
                    UserCostsWindow userPageWindow = new UserCostsWindow();
                    userPageWindow.Show();
                    Hide();
                }

                else
                {
                    MessageBox.Show("Некоректный логин или пароль!");
                }
            }
        }