private ShippingProduct GetShippingProduct()
    {
        var result = new ShippingProduct
        {
            Name   = this.txtProductName.Text,
            Weight = Convert.ToDouble(this.txtProductWeight.Text),
            Size   = new Size
            {
                Length = Convert.ToDouble(this.txtProductLength.Text),
                Width  = Convert.ToDouble(this.txtProductWidth.Text),
                Height = Convert.ToDouble(this.txtProductHeight.Text)
            },
            Shipper = Convert.ToInt32(this.drpCompany.SelectedValue)
        };

        return(result);
    }
        public void CalculateTest()
        {
            //arrange
            var sut     = new BlackCatShipper();
            var product = new ShippingProduct
            {
                Name   = "book",
                Weight = 10,
                Size   = new Size
                {
                    Length = 30,
                    Width  = 20,
                    Height = 10
                },
            };

            //act
            sut.CalculateFee(product);

            //assert
            var expected = 200;

            Assert.AreEqual(expected, product.ShippingFee);
        }