private void btnBackToDo_Click(object sender, RoutedEventArgs e)
        {
            var listWindow = new ListWindow();

            listWindow.Show();
            listWindow.GetUser(userModel);
            this.Close();
        }
        public void UserEnter()
        {
            byte[] data     = Encoding.UTF8.GetBytes(pwdUser.Password);
            var    hashPass = CryptPassword(data);
            var    user     = db.Users.AsQueryable().Where(x => x.Name.Equals(txtUserName.Text) && x.Password.Equals(hashPass)).FirstOrDefault();

            if (user != null)
            {
                MessageBox.Show("Login Success.");
                var listWindow = new ListWindow();
                listWindow.Show();
                listWindow.GetUser(user);
                this.Close();
            }
            else
            {
                MessageBox.Show("Login Failed. Please check your username or password");
            }
        }