Find out which class called a method in another class

Question

Is there a way in PHP to find out what object called what method in another object.

Exmaple:

class Foo {   public function __construct()   {     $bar = new Bar();     $bar->test();   } }  class Bar {   public function test()   {   } } $foo = new Foo(); 

Would there be a way for me to find out that the test method was called from the foo object?

Answer 1

you could use debug_backtrace, a bit like this :
BTW, take a look at the comments on the manual page : there are some useful functions and advices given ;-)

class Foo {   public function __construct()   {     $bar = new Bar();     $bar->test();   } }  class Bar {   public function test()   {       $trace = debug_backtrace();       if (isset($trace[1])) {           // $trace[0] is ourself           // $trace[1] is our caller           // and so on...           var_dump($trace[1]);            echo "called by {$trace[1]['class']} :: {$trace[1]['function']}";        }   } } $foo = new Foo(); 

The var_dump would output :

array   'file' => string '/home/squale/developpement/tests/temp/temp.php' (length=46)   'line' => int 29   'function' => string '__construct' (length=11)   'class' => string 'Foo' (length=3)   'object' =>      object(Foo)[1]   'type' => string '->' (length=2)   'args' =>      array       empty 

and the echo :

called by Foo :: __construct 

But, as nice as it might look like, I am not sure it should be used as a "normal thing" in your application... Seems odd, actually : with a good design, a method should not need to know what called it, in my opinion.