PHP get keys from array in object

Question

I've got object and I need list of it's keys.

for now I doing that in foreach

foreach($obj as $key => $attribute){
  var_dump($key);
}

Is there some PHP built in function for getting object keys like array_keys for arrays?

trace

object(Solarium\QueryType\Select\Result\Document)#1383 (1) { ["fields":protected]=> array(31) { ["pdf_url"]=> string(51) "xxxxxxxxxxxx" ["title"]=> string(150) ......

There is `get_object_vars()` at http://php.net/manual/en/function.get-object-vars.php — arkascha, Sep 22 '16 at 07:18
get_object_vars() return empty array. But foreach do the job. I don't know why. — Stevan Tosic, Sep 22 '16 at 07:20
Possible duplicate of [PHP Print keys from an object?](http://stackoverflow.com/questions/5803881/php-print-keys-from-an-object) — Akshay Khetrapal, Sep 22 '16 at 07:24
Or cast to array (`$arr = (array) $obj;`) then use `array_keys($arr)` — Michael, Sep 22 '16 at 07:25
What is your complexity?? and what you want to do?? _PHP get object keys_ is not enough to help you, share what you have. Your try is correct.. — Murad Hasan, Sep 22 '16 at 07:26

score 4 · Accepted Answer · answered Sep 22 '16 at 07:29

4

class A 
{
    private $a = 1;
    protected $b = 2;
    public $c = 3;
}

$object = new A();
$fields = get_object_vars($object);

But by this method, you can only get public fields from your object, i.e

print_r($fields);

Will output

Array ( [c] => 3 )

answered Sep 22 '16 at 07:29

Svitavsky

291
1
15

I tried get_object_vars but it return empty array. I now see that I wrote wrong question because it was array in object, and there is no public property in obj. – Stevan Tosic Sep 22 '16 at 07:39

score 0 · Answer 2 · answered Sep 22 '16 at 07:30

0

Problem is because it was

array in object.

I solve problem with this

array_keys($obj->getFields())

answered Sep 22 '16 at 07:30

Stevan Tosic

6,561
10
55
110

PHP get keys from array in object

2 Answers2