問題描述

所以我認為一個好的 Laravel 應用程序應該是非常模型驅(qū)動和事件驅(qū)動的.

So the way I see it is that a good Laravel application should be very model- and event-driven.

我有一個名為 Article 的模型.我希望在發(fā)生以下事件時發(fā)送電子郵件警報:

I have a Model called Article. I wish to send email alerts when the following events happen:

• 何時創(chuàng)建文章
• 文章更新時
• 當文章被刪除時

文檔說我可以使用模型事件并在 <AppProvidersEventServiceProvider的code>boot()函數(shù).

The docs say I can use Model Events and register them within the boot() function of AppProvidersEventServiceProvider.

但這讓我很困惑，因為...

But this is confusing me because...

• 當我添加其他模型(如 Comment 或 Author)時，會發(fā)生什么，這些模型需要所有自己的模型事件的完整集合?EventServiceProvider 的單個 boot() 函數(shù)會非常龐大??嗎?
• Laravel 的其他"事件的目的是什么?如果實際上我的事件只會響應模型 CRUD 操作，為什么我還需要使用它們?

• What happens when I add further models like Comment or Author that need full sets of all their own Model Events? Will the single boot() function of EventServiceProvider just be absolutely huge?
• What is the purpose of Laravel's 'other' Events? Why would I ever need to use them if realistically my events will only respond to Model CRUD actions?

我是 Laravel 的初學者，來自 CodeIgniter，所以我試圖圍繞正確的 Laravel 做事方式進行思考.感謝您的建議！

I am a beginner at Laravel, having come from CodeIgniter, so trying to wrap my head around the proper Laravel way of doing things. Thanks for your advice!

推薦答案

最近我在我的 Laravel 5 項目之一中遇到了同樣的問題，我不得不在其中記錄所有模型事件.我決定使用 Traits.我創(chuàng)建了 ModelEventLogger Trait 并簡單地用于所有需要記錄的模型類.我將根據(jù)您的需要更改它，如下所示.

Recently I came to same problem in one of my Laravel 5 project, where I had to log all Model Events. I decided to use Traits. I created ModelEventLogger Trait and simply used in all Model class which needed to be logged. I am going to change it as per your need Which is given below.

<?php

namespace AppTraits;

use IlluminateDatabaseEloquentModel;
use IlluminateSupportFacadesEvent;

/**
 * Class ModelEventThrower 
 * @package AppTraits
 *
 *  Automatically throw Add, Update, Delete events of Model.
 */
trait ModelEventThrower {

    /**
     * Automatically boot with Model, and register Events handler.
     */
    protected static function bootModelEventThrower()
    {
        foreach (static::getModelEvents() as $eventName) {
            static::$eventName(function (Model $model) use ($eventName) {
                try {
                    $reflect = new ReflectionClass($model);
                    Event::fire(strtolower($reflect->getShortName()).'.'.$eventName, $model);
                } catch (Exception $e) {
                    return true;
                }
            });
        }
    }

    /**
     * Set the default events to be recorded if the $recordEvents
     * property does not exist on the model.
     *
     * @return array
     */
    protected static function getModelEvents()
    {
        if (isset(static::$recordEvents)) {
            return static::$recordEvents;
        }

        return [
            'created',
            'updated',
            'deleted',
        ];
    }
} 

現(xiàn)在您可以在要為其拋出事件的任何模型中使用此特征.在您的情況下 Article 模型.

Now you can use this trait in any Model you want to throw events for. In your case in Article Model.

<?php namespace App;

use AppTraitsModelEventThrower;
use IlluminateDatabaseEloquentModel;

class Article extends Model {

    use ModelEventThrower;

    //Just in case you want specific events to be fired for Article model
    //uncomment following line of code

   // protected static $recordEvents = ['created'];

}

現(xiàn)在在您的 app/Providers/EventServiceProvider.php 中，在 boot() 方法中為 Article 注冊事件處理程序.

Now in your app/Providers/EventServiceProvider.php, in boot() method register Event Handler for Article.

 public function boot(DispatcherContract $events)
 {
     parent::boot($events);
     $events->subscribe('AppHandlersEventsArticleEventHandler');
 }

現(xiàn)在在app/Handlers/Events目錄下創(chuàng)建ArticleEventHandler類，

<?php namespace AppHandlersEvents;

use AppArticle;

class ArticleEventHandler{

    /**
     * Create the event handler.
     *
     * @return AppHandlersEventsArticleEventHandler
     */
    public function __construct()
    {
        //
    }

    /**
    * Handle article.created event
    */

   public function created(Article $article)
   {
      //Implement logic
   }

   /**
   * Handle article.updated event
   */

   public function updated(Article $article)
   {
      //Implement logic
   }

  /**
  * Handle article.deleted event
  */

  public function deleted(Article $article)
  {
     //Implement logic
  }

 /**
 * @param $events
 */
 public function subscribe($events)
 {
     $events->listen('article.created',
            'AppHandlersEventsArticleEventHandler@created');
     $events->listen('article.updated',
            'AppHandlersEventsArticleEventHandler@updated');
     $events->listen('article.deleted',
            'AppHandlersEventsArticleEventHandler@deleted');
 }

}

正如您從不同的答案中看到的，來自不同的用戶，處理模型事件的方法不止一種.還有自定義事件，可以在Events文件夾中創(chuàng)建，可以在Handler文件夾中處理，可以從不同的地方分派.希望能幫到你.

As you can see from different answers, from different Users, there are more than 1 way of handling Model Events. There are also Custom events That can be created in Events folder and can be handled in Handler folder and can be dispatched from different places. I hope it helps.

這篇關(guān)于Laravel 模型事件 - 我對它們的去向有點困惑的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網(wǎng)！