- strcmp: documentation ( source)
- strtoupper: documentation ( source)
- usort: documentation ( source)
<?php
$abc = array( 'rec_1' => array('fn'=>'Aron','ln'=>'Michaelson'),
'rec_2' => array('fn'=>'Abbey','ln'=>'Drake'),
'rec_3' => array('fn'=>'Alice','ln'=>'Peterson'));
function SortByLname($a,$b) {
return strcmp( $a['ln'], $b['ln'] );
}
usort($abc, "SortByLname");
foreach ($abc as $item) {
echo strtoupper($item['ln']) . ', ' . $item['fn'] . "\n";
}