I am querying a service if a person have phone number(s) (also maybe not). I have a json string (as return value) like the following:

$json = '{"data":[{"tel1":"1102"},{"tel2":"3220"}],"found":true}';

I convert this string to json_decode() function.

$jd = json_decode($json);

Then I want to get the phone numbers only into an array without keys.

if($jd->found) {
    $o2a = get_object_vars($json);

}
var_dump($o2a);

When I want to see what $o2a holds with var_dump() function, I get the following:

array (size=2)
    'data' => 
        array (size=2)
            0 => 
                object(stdClass)[2]
                public 'tel1' => string '1219' (length=4)
            1 => 
                object(stdClass)[3]
                public 'tel2' => string '2710' (length=4)
    'found' => boolean true

I want to get only the phone numbers into an array at the end like:

$phones = array('1219', '2710');

What makes me stop doing this is that I do not know how many phone numbers one can have. Json array could consist of more or less elements.

$possibleJson1 = '{"data":[],"found":false}'; //no phone number found
$possibleJson2 = '{"data":[{"tel1":"1102"},{"tel2":"3220"},{"tel3":"1112"},{"tel4":"3230"}],"found":true}'; //4 phone numbers found

It may vary 0-to-n, so if it was a constant number I could create that array within a loop.