ByteAether.WeakEvent 1.0.0

WeakEvent

from ByteAether

WeakEvent is a lightweight .NET library that implements the weak event pattern using weak references. It ensures that event subscribers don't prevent garbage collection, avoiding memory leaks.

Key Features

• Weak References: Subscribers are held weakly so they can be garbage-collected when no longer in use.
• Events With or Without Data: Choose between WeakEvent for notifications without data and WeakEvent<TEvent> for events that pass data.
• Automatic Cleanup: Dead subscribers are removed automatically during event publishing.
• Simple API: Intuitive methods for subscribing, unsubscribing, and publishing events.

Installation

Install via NuGet:

dotnet add package ByteAether.WeakEvent

Use the --version option to specify a preview version to install.

Usage

Using the WeakEvent

using ByteAether.WeakEvent;

// Create an instance of the weak event without event data
var myEvent = new WeakEvent();

// Create a subscriber and subscribe
var subscriber = () => Console.WriteLine("Event received!");
myEvent.Subscribe(subscriber);

// Raise the event
await myEvent.PublishAsync();

Using the WeakEvent<TEvent>

using ByteAether.WeakEvent;

// Create an instance of the weak event with event data
var myEvent = new WeakEvent<MyEventData>();

// Create a subscriber and subscribe
var subscriber = (MyEventData data) => Console.WriteLine("Received: " + data.Message);
myEvent.Subscribe(subscriber);

// Raise the event
await myEvent.PublishAsync(new MyEventData("Hello, World!"));

// Define your event data
public record MyEventData(string Message);

API Overview

WeakEvent

• Subscribe(Action handler)
Subscribe(Func<Task> handler)
Subscribe(Func<CancellationToken, Task> handler)
  Subscribes the specified handler to the event. The handler will be invoked when the event is raised, provided that its target is still alive.
• Unsubscribe(Action handler)
Unsubscribe(Func<Task> handler)
Unsubscribe(Func<CancellationToken, Task> handler)
  Unsubscribes the specified handler from the event.
• PublishAsync(CancellationToken cancellationToken = default)
  Raises the event by invoking all live subscribers. Dead subscribers (whose targets have been garbage-collected) are removed.

WeakEvent<TEvent>

• Subscribe(Action<TEvent> handler)
Subscribe(Func<TEvent, Task> handler)
Subscribe(Func<TEvent, CancellationToken, Task> handler)
  Subscribes the specified handler to the event. The handler will be invoked when the event is raised, provided that its target is still alive.
• Unsubscribe(Action<TEvent> handler)
Unsubscribe(Func<TEvent, Task> handler)
Unsubscribe(Func<TEvent, CancellationToken, Task> handler)
  Unsubscribes the specified handler from the event.
• PublishAsync(TEvent eventData, CancellationToken cancellationToken = default)
  Raises the event by invoking all live subscribers with the provided event data. Dead subscribers (whose targets have been garbage-collected) are removed.