private void loginButton_Click(object sender, EventArgs e)
        {
            userName = Convert.ToString(nameTextBox.Text);
            userPassword = Convert.ToString(passwordTextBox.Text);

            if (Form1.correctName == userName && Form1.correctPassword == userPassword)
            {
                Form ls = this.FindForm();
                ls.Controls.Remove(this);

                Second_Screen ss = new Second_Screen();
                ls.Controls.Add(ss);
            }
            else
            {
                errorLabel.Text = "Incorrect username and/or password.";
            }
        }
        private void loginButton_Click(object sender, EventArgs e)
        {
            userName     = Convert.ToString(nameTextBox.Text);
            userPassword = Convert.ToString(passwordTextBox.Text);

            if (Form1.correctName == userName && Form1.correctPassword == userPassword)
            {
                Form ls = this.FindForm();
                ls.Controls.Remove(this);


                Second_Screen ss = new Second_Screen();
                ls.Controls.Add(ss);
            }
            else
            {
                errorLabel.Text = "Incorrect username and/or password.";
            }
        }