RedBus

A simple in memory EventBus / MessageBus library in C# with no dependencies

Nuget

Install-Package Redbus 

Supported Frameworks

• .NET Framework 4.5
• .NET Standard 2.0

Example Usage

There is a generic PayloadEvent class that can be used, or you can use any custom classes that derive from EventBase

private void TestMethod()
{
  IEventBus eventBus = new EventBus();
  eventBus.Subscribe<PayloadEvent<int>>(OnIntEvent); 
  eventBus.Subscribe<CustomEventClass>(OnCustomEvent); 
  
  eventBus.Publish(new PayloadEvent<int>(5)); // OnIntEvent will be invoked
  eventBus.Publish(new CustomEventClass()); // OnCustomEvent will be invoked
  
  
  eventBus.Subscribe<PayloadEvent<string>>(s =>
  {
    Console.WriteLine(s.Payload);
  });
  
  eventBus.Publish(new PayloadEvent<string>("Hello"));
}

private void OnCustomEvent(CustomEventClass customEvent)
{
  Console.WriteLine("Received CustomEvent");
}

private void OnIntEvent(PayloadEvent<int> intEvent)
{
  Console.WriteLine(intEvent.Payload);
}

Note that RedBus does not have WeakReferences implemented, so you must explicitly call Unsubscribe for the event when disposing the subscriber to avoid memory leaks. The Subscribe method returns a SubscriptionToken, this is used when unsubscribing.

IEventBus eventBus = new EventBus();
var token = eventBus.Subscribe<PayloadEvent<string>>(s =>
{
  Console.WriteLine(s.Payload);
});

eventBus.Unsubscribe(token);

Extensions

IEventBus eventBus = new EventBus();
var token = eventBus.Subscribe<PayloadEvent<string>>(s =>
{
  Console.WriteLine(s.Payload);
});

token.Unsubscribe(eventBus)

var payloadEvent = new PayloadEvent<string>("Hello");
payloadEvent.Publish(eventBus);

Configuration

• ThrowSubscriberException

By default, Redbus will catch and swallow any exceptions thrown by subscribers. It's possible to configure Redbus to rethrow any exceptions which occurred in a subscriber method - please note the following:

• This will cause an exception from a subscriber to be thrown for a publisher
• This will/may cause subsequent subscribers to not receive an event/message after a subscriber has thrown an exception.

IEventBus eventBus = new EventBus(new EventBusConfiguration { ThrowSubscriberException = true });