Laravel-mail,无法将变量传递到subject,但它在主体中有效

$body = "Attached is the " .$name. " Report for ".date('Y-m-d');
Mail::raw($body , function ($message) use ($emails,$filepath,$filename) {
    $message->from('noreply@test.com', 'webmail');
    $message->attach(storage_path($filepath.'/'.$filename.'.xlsx'));
    foreach ($emails['to'] as $email) {
        $message->to($email);
    }
    foreach ($emails['cc'] as $email) {
        $message->cc($email);
    }
    $message->subject("Report for " .$name. " account");
});

为什么它在身体里用它而不是在这里用它?