private void btnRegister_Click(object sender, EventArgs e)
 {
     List<string> registrationMessages = RegistrationValidation.validateRegistration(txtBoxFirstName.Text, txtBoxLastName.Text,
         txtBoxUsername.Text, txtBoxPassword.Text, txtBoxRepeatPassword.Text, txtBoxEmail.Text);
     if (registrationMessages.Count == 0) {
         MessageBox.Show("Регистрирахте се успешно!");
         this.Close();
     } else {
         ErrorListView errors = new ErrorListView(registrationMessages);
         errors.ShowDialog();
     }
 }
 private void btnLogin_Click(object sender, EventArgs e)
 {
     LoginValidation login = new LoginValidation(txtBoxUsername.Text, txtBoxPassword.Text);
     User user;
     List<string> loginMessages = login.ValidateUserInput(out user);
     if (loginMessages.Count == 0) {
         this.user = user;
         this.DialogResult = DialogResult.OK;
         this.Hide();
         HomeView homeView = new HomeView(user);
     } else {
         ErrorListView errors = new ErrorListView(loginMessages);
         errors.ShowDialog();
     }
 }