In Laravel, events and listeners decouple application logic by allowing actions to be handled separately. Events signal that something has happened, such as a user registering, while listeners react to those events, like sending a welcome email. 1. You create events using php artisan make:event UserRegistered. 2. Listeners are created with php artisan make:listener SendWelcomeEmail --event=UserRegistered. 3. In the EventServiceProvider, you map events to listeners in the $listen array. 4. Events are dispatched using event(new UserRegistered($user)) or Event::dispatch(). 5. Benefits include cleaner code, reusability, scalability, and support for queued listeners to improve performance by handling tasks asynchronously.
In Laravel, events and listeners are part of a system that allows you to decouple various parts of your application. Instead of writing all logic in one place, like a controller, you can "fire" an event when something happens (like a user registering), and then have one or more listeners react to that event.

This makes your code cleaner and easier to maintain because different actions can be handled separately without cluttering the main logic.
What Are Events?
An event is a signal that something has happened in your application. For example, when a user registers, you might fire a UserRegistered
event. This doesn't do anything by itself — it's just a way to announce that a specific action has taken place.

You can generate an event using Artisan:
php artisan make:event UserRegistered
This creates a new class in app/Events
. You can pass data to the event (like the user object) and use it in any listener that reacts to it.

What Are Listeners?
A listener is a piece of code that waits for a specific event and then performs an action when it hears that event. For instance, after a UserRegistered
event is fired, a listener might send a welcome email or log the registration.
You can create a listener with:
php artisan make:listener SendWelcomeEmail --event=UserRegistered
That will create a listener in app/Listeners
and automatically wire it up in the EventServiceProvider
.
How Do They Work Together?
The magic happens in the EventServiceProvider
. In its $listen
array, you define which listeners should respond to which events.
Here’s what it might look like:
protected $listen = [ 'App\Events\UserRegistered' => [ 'App\Listeners\SendWelcomeEmail', 'App\Listeners\LogUserRegistration', ], ];
When the UserRegistered
event is dispatched, both SendWelcomeEmail
and LogUserRegistration
listeners get called.
To dispatch an event somewhere in your app, like in a controller, you’d write:
event(new UserRegistered($user));
Or using the Event
facade:
Event::dispatch(new UserRegistered($user));
Why Use Events and Listeners?
- Separation of concerns: You keep your controllers and models clean.
- Reusability: You can reuse listeners across multiple events.
- Scalability: As your app grows, it's easier to manage logic spread across events and listeners.
- Queue support: Listeners can be queued to run in the background, improving performance.
For example, sending a welcome email doesn’t need to block the registration process. By queuing the SendWelcomeEmail
listener, the user gets a faster response while the email is sent behind the scenes.
Basically, events and listeners give you a structured way to handle side effects in your application without mixing them into your core logic. It's not complicated, but it does take a bit of setup and planning to use effectively.
The above is the detailed content of What are events and listeners in Laravel?. For more information, please follow other related articles on the PHP Chinese website!

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