static void Main(string[] args)
{
BankCard card = new BankCard(DateTime.Now.AddSeconds(2), 100);
DateTime queryTime = DateTime.Now;
decimal available1 =
card.GetAvailableAmount(20, queryTime); // returns 20
decimal available2 =
card.GetAvailableAmount(20, queryTime.AddSeconds(3)); // returns 0
decimal available3 =
card.GetAvailableAmount(20, queryTime); // returns 20
// Previous implementation - does not compile
//BankCard card = new BankCard()
//{
// ValidBefore = DateTime.Now.AddSeconds(2),
// Balance = 100
//};
//decimal available1 = card.GetAvailableAmount(20); // returns 20
//card.Balance = 15;
//decimal available2 = card.GetAvailableAmount(20); // returns 15
//Thread.Sleep(3000); // three seconds later...
//decimal available3 = card.GetAvailableAmount(20); // returns 0
}
static void Main(string[] args)
{
var card = new BankCard()
{
ValidBefore = DateTime.Now.AddSeconds(2),
Balance = 100
};
Console.WriteLine(card.GetAvailableAmount(20)); // returns 20
card.Balance = 15;
Console.WriteLine(card.GetAvailableAmount(20)); // returns 15
Thread.Sleep(3000); // three seconds later...
Console.WriteLine(card.GetAvailableAmount(20)); // returns 0
var immutableCard = new ImmutableBankCard(DateTime.Now.AddSeconds(2), 100);
var queryTime = DateTime.Now;
Console.WriteLine(immutableCard.GetAvailableAmount(20, queryTime)); // returns 20
Console.WriteLine(immutableCard.GetAvailableAmount(20, queryTime.AddSeconds(3))); // returns 0
Console.WriteLine(immutableCard.GetAvailableAmount(20, queryTime)); // returns 20
}
public SpecificCard(Currency currency, BankCard card) : base(currency)
{
this.Card = card ?? throw new ArgumentNullException(nameof(card));
}