assignnment code frag

private void Button1_Click(object sender, EventArgs e)
        {
            string username = textBox1.Text;
            string password = textBox2.Text;
            string holdername = textBox3.Text;
            string phone = textBox4.Text;
            string gender = comboBox1.SelectedItem.ToString();
            string[] vals = { username, password, holdername, phone, gender, Environment.NewLine };

           if (textBox1.Text == "" || textBox2.Text == "" || textBox3.Text == "" || textBox4.Text == "")
                {
                    MessageBox.Show("Textbox should not left empty");
                    goto exit;
                }
           else   using (StreamWriter sr = new StreamWriter("account.txt", true))
                {
                    sr.Write(string.Join(" ", vals));
                    MessageBox.Show("Account successfully created");
                }
        exit:;
            }