Question

我希望按照sql ORDER BY VALUES()中的特定值对数据集合进行排序，但是在PHP中。我有像这样的数组

$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'),
);

我希望按类型但不按字母顺序排列订单数据，而是按照我指定的特定值排序，按类型other排序，然后按drink排序，然后按fruit排序。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'),
);

我尝试了usort，但我不知道如何与2个值进行比较来实现这一目标。感谢。

Answer 1

您也可以尝试这种方式，

$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： - 阵列

(
    [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
        )

)

Answer 2

是的，您可以使用usort之类的：

$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'),
);

usort($array,function($a,$b){

    //Define the order
    $order = array( 'other' => 0 , 'drink' => 1, 'fruit' => 2 );

    //Compare the order
    return $order[ $a[ 'type' ] ] > $order[ $b[ 'type' ] ];

});

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

这将导致：

Array
(
    [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
        )

)

如果数组中有一些类型，你可以这样做以确保将undefined放在最后一个。

usort($array,function($a,$b){
    $order = array( 'other' => 0 , 'drink' => 1, 'fruit' => 2 );

    $aOrder = isset( $order[ $a[ 'type' ] ] ) ? $order[ $a[ 'type' ] ] : 1000000000000;
    $bOrder = isset( $order[ $b[ 'type' ] ] ) ? $order[ $b[ 'type' ] ] : 1000000000000;

    return $aOrder > $bOrder;
});

如何在PHP中按字段值数组对数组进行排序

2 个答案: