I'm unclear as to what you're trying to do, so I'd recommend looking at the checkout controller if you're trying to duplicate the checkout process.

https://github.com/hotcak...utController.cs#L142

https://github.com/hotcak...utController.cs#L176

Thanks for the links but I already found this solution. I am creating my own cart page and checkout custom page, and for this, I need to calculate the shipping with only one country KSA no need to select the country from the dropdown.

I already achieved it by the following code.

public List shipping_Charges()
{
var HccApp = HccAppHelper.InitHccApp();
var orders =HccApp.OrderServices;
var cart = HccApp.OrderServices.CurrentShoppingCart();

cart.ClearShippingPricesAndMethod();

var country = HccApp.GlobalizationServices.Countries.FindByISOCode("SA");
cart.ShippingAddress.CountryBvin = country.Bvin;
cart.ShippingAddress.RegionBvin = "";

orders.Orders.Update(cart, true);
HccApp.CalculateOrderAndSave(cart);

var shipping = HccApp.OrderServices.FindAvailableShippingRates(cart, HccApp);
return shipping.ToList();

}