Laravel 5.5：如何使用用户ID获取发件人电子邮件并将ID替换为收藏中的电子邮件？

Question

我现在创建函数以从消息表中获取所有当前用户消息。通常我可以使用另一个函数更改当前数组值。例如，我必须以所需格式获取发送日期。还可以使用发件人ID从用户表中获取电子邮件

Current function code

public function user_messages()
{
    $user_id = Auth::user()->id;
    $messages = Message::where('to', $user_id)->get();
    foreach ($messages as $message) 
    {
        echo $message->subject; // Example Subject
        echo $message->message; // Long message text
        echo $message->from;    // Sender id. For example: 2
        echo $message->created_at; // Sended date
    }
    //return $messages;
}

我可以在另一个返回所需视图的Controller上调用此函数吗？

更新问题

现在我写另一个函数来获取电子邮件。这个方法好还是不好？

public function getEmail($id)
{
    return User::where('id', $id)->first()->email;
}

foreach ($messages as $message) 
{
    echo $this->getEmail($message->from)."<br>";
}

Answer 1

您可以在消息中使用雄辩的关系模型添加发送者和接收者功能

public function sender() {
 return $this->belongsTo(User::class, 'from');
}

public function receiver() {
 return $this->belongsTo(User::class, 'to');
}

并根据您的意愿格式化日期：

public function getCreatedAT($value) {
  return $this->attributes['created_at']->toIso8601String();
}

然后你可以访问$ message-> sender和$ message-> receiver来获取电子邮件;

Answer 2

如果我理解你的问题而不是我认为最好的方式，那就是使用范围和关系：

消息模型：

/** 
 * Sender relation 
 *
 * @return User 
 */
public function sender() {
    return $this->belongsTo(User::class, 'from');
}

/** 
 * Receiver relation 
 *
 * @return User 
 */
public function receiver() {
    return $this->belongsTo(User::class, 'to');
}

/** 
 * scope that return only messages which send specific user 
 * @return \Illuminate\Database\Eloquent\Builder
 */
public function scopeSentToUser($query, $user_id == null) 
{ 
    if (!$user_id && !\Auth::check()) {
        throw new \InvalidArgumentException('User ID is undefined');
    } else {
        $user_id = \Auth::id();
    }
    return $query->whereHas('receiver', function($sql) use ($user_id) {
        $sql->where('id', $user_id);
    });
}

任何控制器：

/** @var \Illuminate\Database\Eloquent\Collection $messages Messages which were sent to auth user **/
$messages = Message::sentToUser()->get();

/** @var \Illuminate\Database\Eloquent\Collection $messages Messages which were sent to user 2 **/
$anotherUserMessages = Message::sentToUser(2)->get();

foreach ($messages as $message) 
{
    echo $message->subject; // Example Subject
    echo $message->message; // Long message text
    echo $message->from;    // Sender id. For example: 2
    echo $message->created_at; // Sent date
    var_dump($message->sender); // Sender user model
    var_dump($message->receiver); // Receiver user model
}