private void button1_Click(object sender, EventArgs e) { if (usernameTextBox.Text != "" && PasswordTextBox.Text != "") { if (clientProxy.login(usernameTextBox.Text, PasswordTextBox.Text)) { var topicman = new TopicManForm(usernameTextBox.Text); topicman.Show(); } else { MessageBox.Show("Compte innexistant"); } } }