Question

I have two arrays in PHP. The first array ($author_array) is comprised of user_ids in a particular order, like so: (8, 1, 6)

The second array ($user_results) is comprised of an array of objects like so:

Array (     [0] => stdClass Object         (             [ID] => 1             [user_login] => user1         )     [1] => stdClass Object         (             [ID] => 6             [user_login] => user6         )     [2] => stdClass Object         (             [ID] => 8             [user_login] => user8         ) ) 

I’d like to ‘sort’ the second array so it’s in this order, which matches the order of the values in the first array of (8, 1, 6). So it’d look like this:

Array (     [0] => stdClass Object         (             [ID] => 8             [user_login] => user8         )     [1] => stdClass Object         (             [ID] => 1             [user_login] => user1         )     [2] => stdClass Object         (             [ID] => 6             [user_login] => user6         ) ) 

I’m weak on data structures. How could I do this? 🙂

Thanks in advance for your help!

-Bob

Answer 1

Use usort and provide a custom comparison function which uses the position of the key in your ‘ordering’ array to determine the sort order, e.g. something like:

function cmp($a, $b)  {    global $author_array;     $pos1=array_search ($a->ID, $author_array);    $pos2=array_search ($b->ID, $author_array);     if ($pos1==$pos2)        return 0;    else       return ($pos1 < $pos2 ? -1 : 1);  }   usort($user_results, 'cmp');