Sort a multi-domensional PHP array of objects by key value

arrSortObjsByKey.php

<?php
/**
 * Sort a multi-domensional array of objects by key value
 * Usage: usort($array, arrSortObjsByKey('VALUE_TO_SORT_BY'));
 * Expects an array of objects. 
 *
 * @param String    $key  The name of the parameter to sort by
 * @param String 	$order the sort order
 * @return A function to compare using usort
 */ 
function arrSortObjsByKey($key, $order = 'DESC') {
	return function($a, $b) use ($key, $order) {

		// Swap order if necessary
		if ($order == 'DESC') {
 	   		list($a, $b) = array($b, $a);
 		} 

 		// Check data type
 		if (is_numeric($a->$key)) {
 			return $a->$key - $b->$key; // compare numeric
 		} else {
 			return strnatcasecmp($a->$key, $b->$key); // compare string
 		}
	};
}
?>