Add Payment Information

CartServiceProvider provider = new CartServiceProvider();
// You should get a real user id.            
string userId = Guid.NewGuid().ToString("B");
string anonymousUserId = Guid.NewGuid().ToString("B");
var loadRequest = new 
LoadCartByNameRequest("Website", "MyBasket",userId);
var loadResult = provider.LoadCart(loadRequest);             
CommerceCart cart = loadResult.Cart as CommerceCart;             
// Add the party (address)information.            
CommerceParty party = new CommerceParty()            
{                
ExternalId =Guid.NewGuid().ToString("B"),                
Name = "MyFirstAddress",                
Address1 = "Address 1 field",                
Address2 = "Address 2 field",                
City = "City field",                
Company = "Company field",                
Country = "Country field",                
CountryCode = "CND",                
Email = "[email protected]",                
EveningPhoneNumber = "111 111-1111",                
FaxNumber = "222 222-2222",                
FirstName = "First name field",                
LastName = "Last name field",                
PhoneNumber = "333 333-3333",                
RegionCode = "01",                
RegionName = "Region field",                
State = "State field",                
ZipPostalCode = "HOH OHO"            
};             
AddPartiesRequest request = new AddPartiesRequest(cart, new List<Party> { party });            
var result = provider.AddParties(request);             
party = result.Parties.ElementAt(0) as CommerceParty;             
// Get the payment methods            
CommerceOrderServiceProvider orderProvider = new CommerceOrderServiceProvider();             
GetPaymentMethodsRequest paymentMethodsRequest = new GetPaymentMethodsRequest("en-US");            
var paymentMethodsResult = orderProvider.GetPaymentMethods(paymentMethodsRequest);             
CommercePaymentMethod paymentMethod = paymentMethodsResult.PaymentMethods.ElementAt(0) as CommercePaymentMethod;             
CommerceCreditCardPaymentInfo payment = new CommerceCreditCardPaymentInfo();
payment.CreditCardNumber =  "1111111111111111";            
payment.Amount = 72.70M;             
payment.CreditCardIdentifier = "111";            
payment.CustomerNameOnPayment = "John Smith";            
payment.PartyID = party.ExternalId;            
payment.PaymentMethodID = paymentMethod.ExternalId;            
payment.ExpirationMonth =10;            
payment.ExpirationYear = 2020;             
var paymentRequest = new AddPaymentInfoRequest(cart, new List<PaymentInfo> { payment });            
provider.AddPaymentInfo(paymentRequest);