public void Register(ICitizen citizen)
{
if (citizen.VatId == null || CitizenRegistryHelper.FindCitizenById(citizens, citizenCount, citizen.VatId) == null)
{
if (String.IsNullOrWhiteSpace(citizen.VatId))
{
int birthNumber;
string id;
do
{
birthNumber = CitizenRegistryHelper.GetBirthNumber(citizen.Gender);
id = CitizenRegistryHelper.GenerateVatId(citizen.BirthDate, birthNumber, citizen.Gender);
} while (CitizenRegistryHelper.FindCitizenById(citizens, citizenCount, id) != null);
citizen.VatId = id;
}
if (citizenCount == citizens.Length)
{
Array.Resize(ref citizens, citizens.Length * 2);
}
citizens[citizenCount] = citizen.Clone() as Citizen;
citizenCount++;
lastRegistrationTime = SystemDateTime.Now();
}
else
{
throw new InvalidOperationException();
}
}
public ICitizen this[string id]
{
get
{
if (id == null)
{
throw new ArgumentNullException("id");
}
else
{
return(CitizenRegistryHelper.FindCitizenById(citizens, citizenCount, id));
}
}
}
