private void BtnSave_Click(object sender, EventArgs e)
        {
            Classroom c = new Classroom();

            c.Name     = txtClassroomName.Text;
            c.Capacity = (int)numericCapacity.Value;
            if (dto.Create(c))
            {
                MessageBox.Show("Created");
            }
            else
            {
                MessageBox.Show("Not Created");
            }
        }