传递给 App\Events\NoticeAnnouncement::__construct() 的参数 3 必须是 App\User 的实例

Question

我正在尝试在老师发布通知时向所有学生发送邮件。为此，我在创建通知时调用了一个事件，并通过事件变量传递了通知、教师和用户。但它给出一个错误，说“传递给 App\Events\NoticeAnnouncement::__construct() 的参数 3 必须是 App\User 的实例，给定的 Illuminate\Database\Eloquent\Collection 的实例，在 C:\xampp\htdocs 中调用\iiucsmartclassroom\app\Http\Controllers\Teacher\NoticeController.php”。

这是我的通知控制器：

 public function submitNotice(Request $request){
    $validatedData = $request->validate([
    'notice_title' => 'required|max:255',
    'notice_description' => 'required|max:3000',
    'notice_file.*' => 'mimes:jpg,jpeg,pdf',
    ]);

    $data=array();
    $data['teacher_id']=$request->teacher_id;
    $data['notice_title']=$request->notice_title;
    $data['notice_description']=$request->notice_description;
    $data['notice_post_date']=$request->notice_post_date;
    $data['notice_post_time']=$request->notice_post_time;
    $image=$request->file('notice_file');

    if ($image) {
        $image_name= str::random(5);
        $ext=strtolower($image->getClientOriginalExtension());
        $image_full_name=$image_name.'.'.$ext;
        $upload_path='notices/';
        $image_url=$upload_path.$image_full_name;
        $success=$image->move($upload_path,$image_full_name);
        if ($success) {
            $data['notice_file']=$image_url;
            $notices = DB::table('notices')
                     ->insertGetId($data);

             $notice = Notice::find($notices);
             $teacher = Teacher::find($notice->teacher_id);
             $users = User::all();

             event(new NoticeAnnouncement($notice,$teacher,$users));
          if ($notices) {
             $notification=array(
             'message'=>'Notice Posted Successfully',
             'alert-type'=>'success'
              );
            return Redirect()->back()->with($notification);                      
         }else{
          $notification=array(
             'message'=>'Could not be able to post the Notice',
             'alert-type'=>'error'
              );
             return Redirect()->back()->with($notification);
         }      
            
        }else{

          return Redirect()->back();
            
        }
    }else{
          $notice = DB::table('notices')
                     ->insert($data);
          if ($notice) {
             $notification=array(
             'message'=>'Notice Posted Successfully',
             'alert-type'=>'success'
              );
            return Redirect()->back()->with($notification);                     
         }else{
          $notification=array(
             'message'=>'Could not be able to post the Notice',
             'alert-type'=>'error'
              );
             return Redirect()->back()->with($notification);
         }  
    }
}

这是我的活动：

public $notice,$teacher,$user;
/**
 * Create a new event instance.
 *
 * @return void
 */
public function __construct(Notice $notice,Teacher $teacher,User $user)
{
    $this->notice = $notice;
    $this->teacher = $teacher; 
    $this->user = $user;
}

这是我的听众：

public function handle(NoticeAnnouncement $event)
{
        foreach ($event->user as $user) {
        Mail::to($user->email)->send(new SendNotice($event->notice,$event->teacher,$event->user));
    }
}

Answer 1

您将用户集合发送到方法而不是用户模型：

Mail::to($user->email)->send(new SendNotice($event->notice,$event->teacher,$user));

Answer 2

您使用find($key) 函数从\Illuminate\Database\Eloquent\Collection 获取Illuminate\Database\Eloquent\Model。

public function handle(NoticeAnnouncement $event)
{
        foreach ($event->users as $key => $user) {
        Mail::to($user->email)->send(new SendNotice($event->notice,$event->teacher,$event->users->find($key)));
    }
}