php - 如何在 PHP 中按字段值数组对数组进行排序

Question

我想按特定值对数据集合进行排序，例如在 sql ORDER BY VALUES() 中，但在 PHP 中。我有这样的数组

$array = array(
    array('name' => 'Milk', 'type' => 'drink'),
    array('name' => 'Coffee', 'type' => 'drink'),
    array('name' => 'Orange', 'type' => 'fruit'),
    array('name' => 'Computer', 'type' => 'other'),
    array('name' => 'Water', 'type' => 'other'),
);

我想按类型而不是按字母顺序排序数据，而是按我指定的特定值排序，按 other 类型排序，然后是 drink，然后是 fruit 。所以结果应该是:

 $array = array(
    array('name' => 'Computer', 'type' => 'other'),
    array('name' => 'Water', 'type' => 'other'),
    array('name' => 'Milk', 'type' => 'drink'),
    array('name' => 'Coffee', 'type' => 'drink'),
    array('name' => 'Orange', 'type' => 'fruit'),
);

我试过 usort 但我不知道如何比较 2 个值来实现它。谢谢。

Answer 1

你也可以这样试试，

$array = array(
    array('name' => 'Milk', 'type' => 'drink'),
    array('name' => 'Coffee', 'type' => 'drink'),
    array('name' => 'Orange', 'type' => 'fruit'),
    array('name' => 'Computer', 'type' => 'other'),
    array('name' => 'Water', 'type' => 'other'),
);

// array_flip turns 0 => 'other', 1 => 'drink', ... into 'other' => 0, 'drink' => 1, ...
$order=array_flip(array('other','drink','fruit'));

usort($array, function($x, $y) use($order) {
    if (!isset($order[$x['type']], $order[$y['type']])) {
        // none of the ids have order, so sort by bare type
        return $x['type'] - $y['type'];
    }
    else if (!isset($order[$x['type']])) { 
        // x does not have order, put it last
        return 1;
    }
    else if (!isset($order[$y['type']])) {
        // y does not have order, put it last
        return -1;
    }

    // both have types, use them
    return $order[$x['type']] - $order[$y['type']];
});

echo "<pre>";
print_r($array);

输出:-数组

(
    [0] => Array
        (
            [name] => Computer
            [type] => other
        )

    [1] => Array
        (
            [name] => Water
            [type] => other
        )

    [2] => Array
        (
            [name] => Milk
            [type] => drink
        )

    [3] => Array
        (
            [name] => Coffee
            [type] => drink
        )

    [4] => Array
        (
            [name] => Orange
            [type] => fruit
        )

)