Calling an object from another in PHP using construct

[FarrisFahad]

How can I include objects in each other using PHP OOP?

I have 3 classes all classes make use of one another. I am trying to call them on __construct but it's creating an infinite calls to one another. How can I solve this?

[pritaeas]

Show some code of how you expect it to work.

[Dani]

I'm not understanding your question. You can definitely create objects within the methods of other classes. As pritaeas says, please post some code so we can understand better.

[jkon]

In every OOP language that I know you can create infinite recursive loops in a construction method . Lets play a bit with it in PHP:

class A
{
    private $obj; 

    public function __construct()
    {
        $this->obj = new B();
    }
}

class B
{
    private $obj;

    public function __construct()
    {
        $this->obj = new C();
    }
}

class C
{
    private $obj;

    public function __construct()
    {
        $this->obj = new A();
    }
}

$obj = new C();

But why on earth would you do that ?

[FarrisFahad]

Hey, I know that this discussion is old but I need to know now.
I am new to OOP in PHP. Is it good to call a class within a class? Why or why not?
How should I create an object? I want objects to use other methods from other objects.
Your example is good ...

class A
{
    private $obj; 

    public function __construct()
    {
        $this->obj = new B();
    }
}

class B
{
    private $obj;

    public function __construct()
    {
        $this->obj = new C();
    }
}

class C
{
    private $obj;

    public function __construct()
    {
        $this->obj = new A();
    }
}

$obj = new C();

but I am trying to do the following ...

class A
{
    private $A;
    private $B;
    private $C;

    public function __construct()
    {
        $this->A = new A();
        $this->B = new B();
        $this->C = new C();
    }
}

class B
{
    private $A;
    private $B;
    private $C;

    public function __construct()
    {
        $this->A = new A();
        $this->B = new B();
        $this->C = new C();
    }
}

class C
{
    private $A;
    private $B;
    private $C;

    public function __construct()
    {
        $this->A = new A();
        $this->B = new B();
        $this->C = new C();
    }
}

$A = new A();
$B = new B();
$C = new C();

[pritaeas]

That causes an infinite loop as described by jkon.

I'd go for a container class:

class Container
{
    private $A;
    private $B;
    private $C;

    public function __construct($A, $B, $C)
    {
        $this->A = $A;
        $this->B = $B;
        $this->C = $C;
    }
}

$A = new A();
$B = new B();
$C = new C();
$Container = new Container($A, $B, $C);

https://www.daniweb.com/programming/web-development/tutorials/437592/introduction-to-php-s-object-orientation

[Dani]

I feel like you're going to end up in an infinite loop if you create a new A from the constructor function of class A. Same with class B having new B() in its contruxtor, and and C having new C() in its constructor.

[Dani]

Oh, sorry. I didn't see the post by pritaeas.

[aishamushtaq]

To avoid infinite loops when including objects of multiple classes in PHP OOP:

1. Use dependency injection to pass objects as dependencies.
2. Review class design for circular dependencies.
3. Refactor classes to break cyclic dependencies if necessary.