private void buttonLogin_Click(object sender, EventArgs e)
        {
            if (textBoxUserName.Text == "")
            {
                labelUserNameError.Visible = true;
            }
            else
            {
                labelUserNameError.Visible = false;
            }
            if (textBoxPassword.Text == "")
            {
                labelPasswordError.Visible = true;
            }
            else
            {
                labelPasswordError.Visible = false;
            }
            if (labelUserNameError.Visible || labelPasswordError.Visible)
            {
                MainClass.ShowMessage("Fields with * are mandatory", "Error", "Error"); //Error is the type of message.
            }
            else
            {
                if (Retrievel.GetUserDetails(textBoxUserName.Text, textBoxPassword.Text))
                {
                    HomeScreen obj = new HomeScreen();

                    MainClass.ShowWindow(obj, this, MDI.ActiveForm);
                }
            }
        }