public void EditPromotion(Promotion element, string username, string password)
 {
     IManager<Promotion> business = new PromotionBusiness();
     business.Edit(element, username, password);
 }
 public int AddPromotion(Promotion element, string username, string password)
 {
     IManager<Promotion> business = new PromotionBusiness();
     return business.Add(element, username, password);
 }