有時候需要對一個二維陣列進行排序，自定義對應的排序規則，比如對一個班級裡面的同學，先按身高降序排序，身高相同的，再按體重降序排序。。。

程式碼：

<?php
$array = [
    ["id" => "1", "name" => "a", "age" => "19",],
    ["id" => "2", "name" => "b", "age" => "39",],
    ["id" => "3", "name" => "c", "age" => "9",],
    ["id" => "4", "name" => "d", "age" => "1",],
    [
 
"id" => "5", "name" => "e", "age" => "88",],
    ["id" => "6", "name" => "f", "age" => "65",],
    ["id" => "7", "name" => "g", "age" => "19",],
];

array_multisort(array_column($array,"age"),SORT_DESC,array_column($array,"id"),SORT_DESC,$array);
print_r($array);
?>

上面這個二維陣列，先按年齡（age）降序排序，如果年齡（age）相同的話，再按 id 降序排序

輸出：

Array
(
    [0] => Array
        (
            [id] => 5
            [name] => e
            [age] => 88
        )

    [1] => Array
        (
            [id] => 6
            [name] => f
            [age] => 65
        )

    [
 
2] => Array
        (
            [id] => 2
            [name] => b
            [age] => 39
        )

    [3] => Array
        (
            [id] => 7
            [name] => g
            [age] => 19
        )

    [4] => Array
        (
            [id] => 1
            [name] => a
            [age] => 19
        )

    [5] => Array
        (
            [id] => 3
            [name] => c
            [age] => 9
        )

    [6] => Array
        (
            [id] => 4
            [name] => d
            [age] => 1
        )

)