### Illustrating Open-Instance Delegates in C#

Source: https://github.com/thomaslevesque/weakevent/blob/master/README.md

This snippet provides an example comparing a standard delegate signature with an open-instance delegate signature. Open-instance delegates include an extra parameter for the target instance, which is used internally by WeakEventSource to invoke subscriber methods without holding a strong reference to the target.

```csharp
public delegate void     FooEventHandler(               object sender, FooEventArgs e);
public delegate void OpenFooEventHandler(object target, object sender, FooEventArgs e);
```

--------------------------------

### Declaring a Weak Event using WeakEventSource in C#

Source: https://github.com/thomaslevesque/weakevent/blob/master/README.md

This snippet demonstrates how to declare an event using the WeakEventSource class. It involves creating a private instance of WeakEventSource and implementing the event's add and remove accessors to delegate subscription and unsubscription to the WeakEventSource instance.

```csharp
private readonly WeakEventSource<MyEventArgs> _myEventSource = new WeakEventSource<MyEventArgs>();
public event EventHandler<MyEventArgs> MyEvent
{
    add { _myEventSource.Subscribe(value); }
    remove { _myEventSource.Unsubscribe(value); }
}
```

--------------------------------

### Standard C# Event Declaration

Source: https://github.com/thomaslevesque/weakevent/blob/master/README.md

This snippet shows the typical way to declare an event in C#. This standard approach creates a strong reference from the publisher to the subscriber via the delegate, which can prevent the subscriber from being garbage collected unless explicitly unsubscribed.

```csharp
public event EventHandler<MyEventArgs> MyEvent;
```

--------------------------------

### Raising a Weak Event using WeakEventSource in C#

Source: https://github.com/thomaslevesque/weakevent/blob/master/README.md

This snippet shows how to raise an event that has been declared using WeakEventSource. Instead of directly invoking the event field, you call the Raise method on the WeakEventSource instance, passing the sender and event arguments.

```csharp
private void OnMyEvent(MyEventArgs e)
{
    _myEventSource.Raise(this, e);
}
```

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