如何从PHP的内部对象获取外部对象用于内部对象的属性名称

Question

Okay, so code which is outside my control works like this:

Class A {

   function use_b($b_name) {
       $this ->  $b_name = new B();
   }
}

Class B {
   var $stuff;
}

So that the object of class B is inside of class A and class A will use a passed in name for the property name of the class B property. Class B is totally unaware of the name it has been given and really doesn't need to know. But I need to know it in order to access class B from class A.

I do have enough control over the code that I can create a property for class B and set it to the name class A has given it, if that is possible. Then I can have class B pass it's name back to my function that needs to traverse class B (currently it returns only the outer object, so I have access to class BI just don't know the name it's been given.)

If that made no sense at all, please comment and let me know.

Answer 1

Finding out the members of A that hold instances of B is not that hard. Try this code:

<?php
Class A {
   function use_b($b_name) {
       $this ->  $b_name = new B();
   }
}

Class B {
   var $stuff;
}

$a = new A();
$a->use_b('test');

foreach(get_object_vars($a) as $key=>$val)
    if(get_class($val) == 'B')
        echo $key . " is the member that holds an instance of B";