array intersect for object array php

nice toString function is already implemented and is called serialize ;) so

array_map('unserialize', array_intersect(array_map('serialize', $obj1), array_map('serialize', $obj2)) );

will do the work, example mentioned higher don't work 'cause array_intersect work's only with strings as someone mentioned too

array_intersect() returns an array containing all the values of array1 that are present in all the arguments.

Then what mean present in this context (exacly this function), i found on php.net my answer:

Two elements are considered equal if and only if (string) $elem1 === (string) $elem2. In words: when the string representation is the same.

Then you can't use it on array of objects if your objects not implements unique conversion to string.

The correct way to check whether two objects are equal is to use ==. Therefore:

array_uintersect($arr1, $arr2, function ($a1, $a2) { return $a1 == $a2; });

Had a similar problem a few days ago, while these are answers are on the right path; I used them to work out the following:

From Artefacto's answer return $obj1 == $obj2 didn't really work, so I wrote a simple comparative function (basically gets the md5 of the serialised object and compares that):

function object_compare($obj1, $obj2){
  $md5 = function($obj){
    return md5(serialize($obj));
  };
  return strcmp($md5($obj1), $md5($obj2));
}

Then it’s jut a matter of calling array_uintersect with our comparative function to get the intersection:

# $array1 / $array2 are the array of objects we want to compare
return array_uintersect($array1, $array2, 'object_compare');

In my case, I had an unknown / dynamic array of objects, so I took it a step further so I don't have to declare array_uintersect($array1, $array2, ...) specifically - but just be able to pass in an array of arrays (of objects):

# $multiarray_of_objects is our array of arrays
$multiarray_of_objects[] = 'object_compare';
return call_user_func_array('array_uintersect', $multiarray_of_objects);

Just gotta remember to pass in the reference to our callback / comparative function as the last string in the array. Works like a charm!