public static void Insert(ProductSupply productSupply)
        {
            using (var db = OnlineStoreDbContext.Entity)
            {
                db.ProductSupplies.Add(productSupply);

                db.SaveChanges();
            }
        }
        public static void Update(ProductSupply productSupply)
        {
            using (var db = OnlineStoreDbContext.Entity)
            {
                var orgProductSupply = db.ProductSupplies.Where(item => item.ID == productSupply.ID).Single();

                orgProductSupply.ProductID   = productSupply.ProductID;
                orgProductSupply.Count       = productSupply.Count;
                orgProductSupply.SupplyType  = productSupply.SupplyType;
                orgProductSupply.Description = productSupply.Description;
                orgProductSupply.LastUpdate  = productSupply.LastUpdate;

                db.SaveChanges();
            }
        }