public void TestUpdateDiscount_OnlyRequired()
        {
            var ud = new UpdateDiscount {DiscountCode = "1"};

            string actual = ud.Serialize();
            const string expected = @"
            <discountCode>1</discountCode>";
            Assert.AreEqual(expected, actual);
        }
        public void TestUpdateDiscount_Full()
        {
            var ud = new UpdateDiscount
            {
                DiscountCode = "1",
                Name = "cheaper",
                Amount = 200,
                StartDate = new DateTime(2013, 9, 5),
                EndDate = new DateTime(2013, 9, 6)
            };

            string actual = ud.Serialize();
            const string expected = @"
            <discountCode>1</discountCode>
            <name>cheaper</name>
            <amount>200</amount>
            <startDate>2013-09-05</startDate>
            <endDate>2013-09-06</endDate>";
            Assert.AreEqual(expected, actual);
        }