public int UpdatePorductQuantity(CartItemC cartItem)
        {
            SqlConnection connection = new SqlConnection(connectionString);

            if (cartItem.ProductSize == null)
            {
                String     QUERY   = "UPDATE products SET Quantity =Quantity -" + cartItem.Qty + " WHERE ProductId =" + cartItem.ProductId;
                SqlCommand command = new SqlCommand(QUERY, connection);
                connection.Open();
                int res = command.ExecuteNonQuery();
                connection.Close();

                return(res);
            }
            else
            {
                if (cartItem.ProductSize.Equals("L"))
                {
                    String     QUERY   = "UPDATE products SET LCount =LCount -" + cartItem.Qty + " WHERE ProductId =" + cartItem.ProductId;
                    SqlCommand command = new SqlCommand(QUERY, connection);
                    connection.Open();
                    int res = command.ExecuteNonQuery();
                    connection.Close();

                    return(res);
                }
                else if (cartItem.ProductSize.Equals("M"))
                {
                    String     QUERY   = "UPDATE products SET MCount =MCount -" + cartItem.Qty + " WHERE ProductId =" + cartItem.ProductId;
                    SqlCommand command = new SqlCommand(QUERY, connection);
                    connection.Open();
                    int res = command.ExecuteNonQuery();
                    connection.Close();

                    return(res);
                }
                else if (cartItem.ProductSize.Equals("XL"))
                {
                    String     QUERY   = "UPDATE products SET XLCount =XLCount -" + cartItem.Qty + " WHERE ProductId =" + cartItem.ProductId;
                    SqlCommand command = new SqlCommand(QUERY, connection);
                    connection.Open();
                    int res = command.ExecuteNonQuery();
                    connection.Close();

                    return(res);
                }
                else if (cartItem.ProductSize.Equals("XXL"))
                {
                    String     QUERY   = "UPDATE products SET XXLCount =XXLCount -" + cartItem.Qty + " WHERE ProductId =" + cartItem.ProductId;
                    SqlCommand command = new SqlCommand(QUERY, connection);
                    connection.Open();
                    int res = command.ExecuteNonQuery();
                    connection.Close();

                    return(res);
                }
            }

            return(-1);
        }
        public int insertCartItem(CartItemC cartItem)
        {
            SqlConnection connection = new SqlConnection(connectionString);
            String        Query      = "INSERT INTO CartItems VALUES (" + cartItem.OrderId + "," + cartItem.ProductId + ",'" + cartItem.ProductImage + "','" + cartItem.ProductName + "','" + cartItem.ProductSize + "'," + cartItem.UnitPrice + "," + cartItem.Qty + "," + Convert.ToDouble(cartItem.Subtotal) + ")";
            SqlCommand    command    = new SqlCommand(Query, connection);

            connection.Open();
            int res = command.ExecuteNonQuery();

            connection.Close();

            return(res);
        }