Event trong Laravel là gì và cách sử dụng?

Event cho phép giao tiếp loosely coupled—khi điều gì đó xảy ra (event UserCreated), các listener phản ứng.

• Tạo event: php artisan make:event UserCreated với property public $user.
• Tạo listener: php artisan make:listener SendWelcomeEmail --event=UserCreated.
• Dispatch từ model: UserCreated::dispatch($user).
• Listener thực thi đồng bộ theo mặc định, hoặc queue với implements ShouldQueue.
• Event tách biệt code—logic tạo user không biết về email, notification. Laravel 11+: EventServiceProvider đã bị xóa—listener đăng ký trong AppServiceProvider qua Event::listen() hoặc dùng auto-discovery (event discovery tự động).

Events enable decoupled communication—when something happens (UserCreated event), listeners react.

• Create event: php artisan make:event UserCreated with public $user property.
• Create listener: php artisan make:listener SendWelcomeEmail --event=UserCreated.
• Dispatch from model: UserCreated::dispatch($user).
• Listeners execute synchronously by default, or queue with implements ShouldQueue.
• Events decouple code—user creation logic doesn't know about emails, notifications. Laravel 11+: EventServiceProvider was removed — listeners are registered in AppServiceProvider via Event::listen() or use automatic event discovery.