.NET Core 2.0 Event Bus A simple memory event bus implementation

9. Test cases

namespace MemoryMqTest
{
 public class EventHandler: IE ventHandler
 {
 public Task Handle(IEvent e, MessagingHelper h) 
 {
 switch (e)
 {

 case Order value: Console.WriteLine(value.name); break ;
 
 }
 return< span style="color: #000000"> Task.CompletedTask;

 }

 }
 public class Order: IEvent
 {
 < span style="color: #0000ff">public string name {get; set; }
 }
 class< /span> Program
 {
 static void Main(string[] args)
 {
 var servicecollection = new ServiceCollection();
 servicecollection.AddSingleton();
 servicecollection.AddSingleton();
 var provider = servicecollection.BuildServiceProvider();

 var eventPub = provider.GetService();

 var _eventSub = provider.GetService();

 _eventSub.Subscribe();


 var order = new Order();
 order.name = "test";
 eventPub.Publish(order);

 Console.WriteLine("Hello World!");

 Console.ReadKey();
 }
 }
}

10. Test results

public interface IEvent
 {
 
 }

 public interface IEventHandler : IEvent
 {
 Task Handle(IEvent e);
 }

public interface IEventPublisher
 {
 Task Publish (TEvent e) where TEvent: IEvent;
 }

public interface IEventSubscriber 
 {
 
 Task Subscribe() where TEvent: IEvent where EH: class, IEventHandler, new< /span>();
 }

 public static class MemoryMq 
 {
 public static ConcurrentDictionary<string, IEvent> eventQueueDict {get; set; }

 }

 public class InMemoryEventPublisher: IEventPublisher
 {
 public Task Publish(TEvent @event) where TEvent: IEvent
 {
 if (@event == null) return Task.CompletedTask;
 if (MemoryMq.eventQueueDict == null)
 {
 MemoryMq.eventQueueDict = new ConcurrentDictionary<string, IEvent>();
 }
 MemoryMq.eventQueueDict.GetOrAdd (Guid.NewGuid().ToString(),@event);
 return Task.CompletedTask;
 }
 }

public class InMemoryEventSubscriber: IEventSubscriber 
 {
 private readonly ConcurrentDictionary<string, Task> taskDict = new ConcurrentDictionary<string span>, Task>();

 

  public Task Subscribe() where TEvent: IEvent
 where EH: class, IEventHandler,  new()
 {
 
 EH state = new EH();
 

 
 Task.Run(() =>
 {
 while (true)
 {
 if (MemoryMq.eventQueueDict != null)
 {
 foreach (var a in MemoryMq.eventQueueDict) 
 {
 state.Handle(a.Value as< /span> IEvent);
 IEvent o;
 MemoryMq.eventQueueDict.TryRemove(a .Key ,out o);
 }
 }

 }
 
 });
 
 return Task.CompletedTask;
 }
 }

namespace  MemoryMqTest
{
 public class EventHandler: IEventHandler
 {
 public  Task Handle(IEvent e, MessagingHelper h)
 {
 switch (e)
 {

 case Order value: Console.WriteLine(value.name); break ;
 
 }
 return Task.CompletedTask;

 }

 }
 public span> class Order: IEvent
 {
 public string name {get; set; }
 }
 class  Program
 {
 static void Main(string[] args)
 {
 var< /span> servicecollection = new ServiceCollection();
 servicecollection.AddSingleton();
 servicecollection.AddSingleton();
 var provider = servicecollection.BuildServiceProvider();

 var eventPub = provider.GetService();

 var< /span> _eventSub = provider.GetService();

 _eventSub.Subscribe();


 var order = new Order();
 order.name = "test";
 eventPub.Publish(order);

 Console.WriteLine(" Hello World!");

 Console.ReadKey(); 
 }
 }
}