If you have array like this
Array
(
[0] => stdClass Object
(
[page_id] => 269
)
[1] => stdClass Object
(
[page_id] => 887
)
[2] => stdClass Object
(
[page_id] => 544
)
)
Solution
$converted_arr = json_decode(json_encode($your_stdobj_array), true);
OR
foreach ($your_stdobj_arrayas $value){
$array[] = $value->page_id;
}