静态类DomainEvents:
public static class DomainEvents
{
[ThreadStatic]
private static List<Delegate> _actions;
private static List<Delegate> Actions
{
get
{
if (_actions == null)
{
_actions = new List<Delegate>();
}
return _actions;
}
}
public static IDisposable Register<T>(Action<T> callback)
{
Actions.Add(callback);
return new DomainEventRegistrationRemover(
() => Actions.Remove(callback)
);
}
public static void Raise<T>(T eventArgs)
{
foreach(Delegate action in Actions)
{
(action as Action<T>)?.Invoke(eventArgs);
}
}
private sealed class DomainEventRegistrationRemover : IDisposable
{
private readonly Action _callOnDispose;
public DomainEventRegistrationRemover(Action toCall)
{
_callOnDispose = toCall;
}
public void Dispose()
{
_callOnDispose();
}
}
}
实体OrderForDelivery：
public class OrderForDelivery
{
public Guid OrderId { get; set; }
public FoodDeliveryOrderSteps Status { get; set; }
public DateTime TimeThatPizzaWasDeliverd { get; set; }
public DateTime TimeOfOrderBeingPlaced { get; set; }
//public delegate void DeliveryGuaranteeFailedHandler(DeliveryGuaranteeFailed evnt);
//public event DeliveryGuaranteeFailedHandler DeliveryGuaranteeFailed;
public void ConfirmReceipt(DateTime timeThatPizzaWasDelivered)
{
if(Status!=FoodDeliveryOrderSteps.Delivered)
{
TimeThatPizzaWasDeliverd = timeThatPizzaWasDelivered;
Status = FoodDeliveryOrderSteps.Delivered;
if(DeliveryGuaranteeOffer.IsNotSatisfiedBy(TimeOfOrderBeingPlaced,TimeThatPizzaWasDeliverd))
{
DomainEvents.Raise(new DeliveryGuaranteeFailed(this));
}
}
}
}
仓储MyOrderRepository：
public class MyOrderRepository : IOrderRepository
{
private List<OrderForDelivery> orderList=new List<OrderForDelivery>();
public void AddOrder(OrderForDelivery order)
{
orderList.Add(order);
}
public OrderForDelivery FindBy(Guid orderId)
{
return orderList.SingleOrDefault(x => x.OrderId == orderId);
}
}
仓储接口IOrderRepository：
public interface IOrderRepository
{
OrderForDelivery FindBy(Guid orderId);
}
领域服务ConfirmDeliveryOfOrder：
public class ConfirmDeliveryOfOrder
{
private IOrderRepository orderRepository;
public ConfirmDeliveryOfOrder(IOrderRepository repo)
{
this.orderRepository = repo;
}
public void Confirm(DateTime timeThatPizzaWasDelivered,Guid orderId)
{
using (DomainEvents.Register<DeliveryGuaranteeFailed>(onDeliveryFailure))
{
var order = orderRepository.FindBy(orderId);
order.ConfirmReceipt(timeThatPizzaWasDelivered);
}
}
private void onDeliveryFailure(DeliveryGuaranteeFailed evnt)
{
Console.WriteLine("送餐超时了...");
}
}
错误定义DeliveryGuaranteeFailed：
public class DeliveryGuaranteeFailed
{
public DeliveryGuaranteeFailed(OrderForDelivery order)
{
this.Order = order;
}
public OrderForDelivery Order { get; private set; }
}
状态枚举FoodDeliveryOrderSteps：
public enum FoodDeliveryOrderSteps
{
UnDeliver,
Delivered
}
条件判断DeliveryGuaranteeOffer:
public class DeliveryGuaranteeOffer
{
public static bool IsNotSatisfiedBy(DateTime timeOfOrderBeingPlaced, DateTime timeThatPizzaWasDeliverd)
{
return timeOfOrderBeingPlaced < timeThatPizzaWasDeliverd;
}
}
应用层Main()：
static void Main(string[] args)
{
OrderForDelivery order = new OrderForDelivery()
{
OrderId = Guid.NewGuid(),
Status = FoodDeliveryOrderSteps.UnDeliver,
TimeOfOrderBeingPlaced = , , , , , )
};
MyOrderRepository repo = new MyOrderRepository();
repo.AddOrder(order);
ConfirmDeliveryOfOrder confirm = new ConfirmDeliveryOfOrder(repo);
confirm.Confirm(, , , , , ), order.OrderId);
Console.ReadKey();
}
不使用DomainEvents:
public class OrderForDelivery
{
public Guid OrderId { get; set; }
public FoodDeliveryOrderSteps Status { get; set; }
public DateTime TimeThatPizzaWasDeliverd { get; set; }
public DateTime TimeOfOrderBeingPlaced { get; set; }
public delegate void DeliveryGuaranteeFailedHandler(DeliveryGuaranteeFailed evnt);
public event DeliveryGuaranteeFailedHandler DeliveryGuaranteeFailed;
public void ConfirmReceipt(DateTime timeThatPizzaWasDelivered)
{
if(Status!=FoodDeliveryOrderSteps.Delivered)
{
TimeThatPizzaWasDeliverd = timeThatPizzaWasDelivered;
Status = FoodDeliveryOrderSteps.Delivered;
if(DeliveryGuaranteeOffer.IsNotSatisfiedBy(TimeOfOrderBeingPlaced,TimeThatPizzaWasDeliverd))
{
//DomainEvents.Raise(new DeliveryGuaranteeFailed(this));
DeliveryGuaranteeFailed(new DomainService.DeliveryGuaranteeFailed(this));
}
}
}
public class ConfirmDeliveryOfOrder
{
private IOrderRepository orderRepository;
public ConfirmDeliveryOfOrder(IOrderRepository repo)
{
this.orderRepository = repo;
}
public void Confirm(DateTime timeThatPizzaWasDelivered,Guid orderId)
{
var order = orderRepository.FindBy(orderId);
order.DeliveryGuaranteeFailed += onDeliveryFailure;
order.ConfirmReceipt(timeThatPizzaWasDelivered);
//using (DomainEvents.Register<DeliveryGuaranteeFailed>(onDeliveryFailure))
//{
// var order = orderRepository.FindBy(orderId);
// order.ConfirmReceipt(timeThatPizzaWasDelivered);
//}
}
private void onDeliveryFailure(DeliveryGuaranteeFailed evnt)
{
Console.WriteLine("送餐超时了...");
}
}