PHP如何在数据相等时按两列排序

function customSort($a, $b) {
    if ($a['column1'] == $b['column1']) {
        return $a['column2'] - $b['column2'];
    }
    return $a['column1'] - $b['column1'];
}

$array = array(
    array('column1' => 1, 'column2' => 2),
    array('column1' => 2, 'column2' => 1),
    array('column1' => 1, 'column2' => 1)
);

usort($array, 'customSort');

foreach ($array as $item) {
    echo $item['column1'] . ' ' . $item['column2'] . '<br>';
}

$column1 = array(1, 2, 1);
$column2 = array(2, 1, 1);

array_multisort($column1, $column2);

for ($i = 0; $i < count($column1); $i++) {
    echo $column1[$i] . ' ' . $column2[$i] . '<br>';
}