当数据库中的某些东西在Laravel中发生变化时，如何触发事件？

// 1. 创建事件类
namespace App\Events;

use Illuminate\Contracts\Events\Dispatcher;
use Illuminate\Foundation\Events\Dispatchable;
use Illuminate\Queue\SerializesModels;

class DatabaseChanged
{
    use Dispatchable, SerializesModels;

    public $data;

    public function __construct($data)
    {
        $this->data = $data;
    }
}

// 2. 定义事件监听器
namespace App\Listeners;

use App\Events\DatabaseChanged;

class SendNotification
{
    public function handle(DatabaseChanged $event)
    {
        // 处理事件发生时的逻辑
        // 可以访问$event->data来获取事件传递的数据
    }
}

// 3. 注册事件和监听器
namespace App\Providers;

use App\Events\DatabaseChanged;
use App\Listeners\SendNotification;
use Illuminate\Support\Facades\Event;
use Illuminate\Foundation\Support\Providers\EventServiceProvider as ServiceProvider;

class EventServiceProvider extends ServiceProvider
{
    protected $listen = [
        DatabaseChanged::class => [
            SendNotification::class,
        ],
    ];

    public function boot()
    {
        parent::boot();
    }
}

// 4. 触发事件
event(new DatabaseChanged($data));