c#继承父类技巧,并增加新的实现

1 父类  partial class FormBillTemplet:Form
        /// <summary>
        /// 新单
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public  virtual   void  tsButtonNewBill_Click(object sender, EventArgs e)
        {
           Messagebox.Show("父亲类")
        }
2、 子类
  public partial class Form3 : MMS.Public.Controls .FormBillTemplet
 public override void tsButtonNewBill_Click(object sender, EventArgs e)
        {
           base.tsButtonNewBill_Click(sender, e);
           MessageBox.Show("新单");
         }
运行，点 tsButtonNewBill按钮则提示：
  Messagebox.Show("父亲类")
 MessageBox.Show("新单");