Storing php object's property in another object as a reference

$this->obj = new Property($this->name);

Is called at the time of object creation. Which is executed before the assignment. i.e. When you call $x = new Type; The constructor is called and you try to copy 'name' which is empty by then

May be what you want it following, rather than passing the value, pass $this and keep the referance.

<?php


class Type
{
    public $obj; //Instance of Property (Property class defined below)
    public $name;

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

class Property
{
    public $value;

    function __construct($ref)
    {
        $this->value = $ref;
    }
}


$x = new Type;
$x->name = 'abcd';

echo "x.name=" . $x->name . '<br/>';
echo "x.obj.name=" . $x->obj->value->name . '<br/>';

While at the time of answering this question is 9+ years old, I've encountered a similar issue today and found a way to do what's requested.

In short: you should use references. Here's a a working example (PHP 8):

<?php

class Source
{
    public int $counter = 10;
}

class Consumer
{
    public int $value = 0;

    public function __construct(int &$value)
    {
        $this->value = &$value;
    }
}

$source = new Source();
// Pass property of Source instance to the consumer.
$consumer = new Consumer($source->counter);

assert($consumer->value === 10);
// Changing value in the Source instance.
$source->counter = 15;
// ... and value in the consumer updated as well.
assert($consumer->value === 15);

exit;

So, the answer is yes, it is possible.

You can pass the name value inside the constructor.

$x = new Type('abcd');

Without doing that, your constructor will not know what $this->name is yet. So we use it in the constructor and set the classes property before using it.

function __construct($p_name){
  $this->name = $p_name;
  $this->obj = new Property($this->name);
}

You could just as easily set the value after calling the constructor and then initialize the reference afterwards -

class Type {
  public $obj;
  public $name;

  function setProperty(){
    $this->obj = new Property($this->name);
  }
}

$x = new Type;
$x->name = 'abcd';
$x->setProperty();

echo "x.name=" . $x->name;
echo "x.obj.name=" . $x->obj->value;

This is an old question but just to add to this.

You can have an object with methods and properties inside of another object..

Example

$obj1 = new class1();

$obj2 = new class2($obj1); // you just grabbed $obj1 and stuck it inside $obj2

Now you can use the stored object's methods like so:

$obj2->obj1->method_from_obj1();

or access the stored object's properties like so:

$obj2->obj1->property_of_obj1; 

This is SUPER convenient if you instantiated an object of some API and want to use the API methods inside of your own object.