php array_multisort not sorting my multidimensional array - php

Question

Array
(
[0] => Array
(
[id] => 7
[workorder_id] => 27
[truck_id] => 4
[event_type] => 1
[location_id] =>
[location_name] => Billing Address
[address_address] => 123 Main Street
[address_city] => Montreal
[address_state] => QC
[address_zip] => A1A1A1
[address_country_id] => 1
[contact] => bob
[phone] => 555-555-555
[fax] => 555-555-555
[po] => 123131
[notes] =>
[appointment_from] => 2013-03-30 12:30:00
[appointment_to] => 2013-03-30 14:30:00
[crossdock] => 0
[status] => 1
)
[1] => Array
(
[id] => 8
[workorder_id] => 27
[truck_id] => 4
[event_type] => -1
[location_id] =>
[location_name] => Billing Address
[address_address] => 123 Main Street
[address_city] => Montreal
[address_state] => QC
[address_zip] => A1A1A1
[address_country_id] => 1
[contact] =>
[phone] => 555-555-555
[fax] =>
[po] =>
[notes] =>
[appointment_from] => 2013-04-04 06:00:00
[appointment_to] => 2013-04-04 12:00:00
[crossdock] => 0
[status] => 1
)
[2] => Array
(
[id] => 9
[workorder_id] => 27
[truck_id] => 4
[event_type] => 1
[location_id] =>
[location_name] => Billing Address
[address_address] => 123 Main Street
[address_city] => Montreal
[address_state] => QC
[address_zip] => A1A1A1
[address_country_id] => 2
[contact] => Jim Smith
[phone] => 555-555-555
[fax] => 555-555-555
[po] =>
[notes] =>
[appointment_from] => 2013-04-16 10:00:00
[appointment_to] => 2013-04-16 12:00:00
[crossdock] => 0
[status] => 1
)
)
Okay, so I have this array, lets call it $array.
I now have a function to sort multidimensional arrays by multiple keys.
function sort_multiple_keys($array,$key1,$key1_sort = SORT_DESC,$key2,$key2_sort = SORT_ASC){
$sort = array();
if(count($array) > 0){
foreach($array as $k=>$v) {
$first[$k] = $v[$key1];
$second[$k] = $v[$key2];
}
array_multisort($first, $key1_sort, $second, $key2_sort, $array);
}
unset($sort);
}
So, I would to sort it by the EVENT TYPE and then APPOINTMENT_FROM date. So I run this function:
sort_multiple_keys($array,'event_type',SORT_DESC,'appointment_from',SORT_ASC);
But nothing??
Any help?

Answer 1

You're not actually returning a value from your sort function.
You can either return $array at the end; or pass it in as a reference, so the function works on the original instance instead of a copy; for that, you need to change the function definition to:
function sort_multiple_keys(&$array,$key1,$key1_sort = SORT_DESC,$key2,$key2_sort = SORT_ASC){
^ tells PHP that this variable is by reference