php - Laravel 修改集合数据

Question

我想知道 Laravel 是否有任何帮助来修改集合。
我需要做的是使用 paginate() 进行查询然后检查登录的用户 ID 是否与发送者或接收者匹配，并基于此向输出添加一个新值:

$userId = Auth::guard('api')->user()->user_id;
$allMessages = Conversation::join('users as sender', 'conversations.sender_id', '=', 'sender.user_id')
                               ->join('users as reciver', 'conversations.recipient_id', '=', 'reciver.user_id')
                               ->where('sender_id',$userId)->orWhere('recipient_id',$userId)
                               ->orderBy('last_updated', 'desc')
                               ->select('subject','sender_id','recipient_id', 'sender_unread', 'recipient_unread', 'last_updated', 'reciver.username as receivername', 'sender.username as sendername')
                               ->paginate(20);

现在我想做一些类似的事情:

if ($allMessages->sender_id == $userId) {
    // add new value to output
    newField = $allMessages->sendername
} else {
    // add new value to output
    newField = $allMessages->receivername
}

然后发送添加了新值的数据

return response()->json(['messages' => $allMessages], 200);

这可能吗？

Answer 1

为此，您最好使用 Collection 类的内置函数。例如，map功能就完美了。

https://laravel.com/docs/5.3/collections#method-map

$allMessages = $allMessages->map(function ($message, $key) use($userId) {
    if ($message->sender_id == $userId) {
        $message->display_name = $message->receivername;
    } else {
        $message->display_name = $message->sendername;
    }

    return $message;
});