Upload file with contact form in Laravel and send email

I try to upload un file and attach it to the email I send But it does not work.

In my MailFile.php (created with php artisan make:mail)

public function __construct(Request $request)
{
    $this->namePdf        = $request->input('name-pdf');
    $this->subjectPdf     = $request->input('subject-pdf');
    $this->emailPdf       = $request->input('email-pdf');
    $this->filePdf        = $request->input('file-pdf');
}


public function build()
{
    return $this->view('mails.sendFile')
                ->subject($this->subjectPdf)
                ->from('test@test.be', 'John Doe')
                ->attach($this->filePdf->getRealPath(), [
                    'as' => 'file.' . $this->filePdf->getClientOriginalExtension(),
                    'mime' => $this->filePdf->getMimeType()
                ]);
}

But it does not work. And I feel like I'm not using the right metod. Can you help me ?

via Jeremy