使用收集 function 创建的 Laravel 集合未在私有属性上添加过滤器

Question

I have used the collect(array) function on $contacts to convert to the collection and use where condition to find the object on criteria of contactId

class Contact {
    private $contactId;

    private $name;

    private $email;

    public function __construct($contactId, $name, $email) {
        $this->contactId = $contactId;
        $this->name = $name;
        $this->email = $email;
    }

    public function setContactId($contactId) {
        $this->contactId = $contactId;

        return $this;
    }

    public function getContactId() {
        return $this->contactId;
    }

    public function setName($name) {
        $this->name = $name;

        return $this;
    }

    public function getName() {
        return $this->name;
    }

    public function setEmail($email) {
        $this->email = $email;

        return $this;
    }

    public function getEmail() {
        return $this->email;
    }
}

$contacts = [];

$contacts[] = new Contact(1, "contact 1", "contact1@test.com");
$contacts[] = new Contact(2, "contact 2", "contact2@test.com");
$contacts[] = new Contact(3, "contact 3", "contact3@test.com");

I have used collect(array) function on $contacts to convert to the collection and used where condition to find the object. but it returned null.

  $contact = $contacts->where('contactId', 1)->first()

I found that upon changing the contactId property to "public" access I got the object from my query.

Contact {#347
  +contactId: 1
  -name: "contact 1"
  -email: "contact1@test.com"
}

I am still confused why collection cannot access the private attribute, it should access it through getter of the attribute. If I am changing the attributes access, the possibly i am going against encapsulation.

Answer 1

The whole point of private attribute is that nobody can access it outside class. So only public can be accessed from outside.

Answer 2

As you are using laravel collection you can use filter and provide condition on the getter function.

collect($contacts)->filter(function ($q){
            return $q->getContactId()==1;
        });

Or if you want only the first then

collect($contacts)->filter(function ($q){
            return $q->getContactId()==1;
        })->first();