Use Delegates and Events

Compose typed callbacks while controlling capture and subscription lifetime.

Typed callables

Action, Func, Predicate and EventHandler-shaped APIs provide compile-time typed callback patterns. They are not late-bound managed delegates.

Design lifetime explicitly

• Prefer value captures for immutable data.
• Use weak ownership when a callback can outlive its target.
• Unsubscribe or cancel before destroying an object referenced by the callback.
• Treat async callbacks and timer handlers as concurrency boundaries.

Composition

Delegate composition can model multicast behavior for the implemented subset, but exception propagation, removal identity and concurrent modification deserve tests in the consumer’s use case.