按键值对数组进行排序PHP

Question

我有这个数组：

Array
(
    [Alben] => Array
        (
            [Sgt._Pepper’s_Lonely_Hearts_Club_Band] => 
            [Rubber_Soul] => 
            [Please_Please_Me] => 
            [Let_It_Be_(Album)] => 
            [With_the_Beatles] => 
            [Let_It_Be…_Naked] => 
            [A_Hard_Day’s_Night_(Album)] => Rickenbacker_360-12WB_12_String.jpg
            [Beatles_for_Sale] => 
            [Help!_(Album)] => Semaphore_Victor.svg
            [Magical_Mystery_Tour_(Album)] => 
            [The_Beatles_(Album)] => 
            [Yellow_Submarine] => 
            [Abbey_Road] => The_End.jpg
            [Revolver_(Album)] => 
            [Anthology_(The_Beatles)] => 
            [A_Collection_of_Oldies_…_but_Goldies] => 
            [1_(Album)] => 
        )

)

现在，我想按值对它进行排序。 因此，这些键是第一个在值中具有img的键。 以及没有这些条目的条目。 我尝试了array_values但它返回了相同的Array。 也许会导致钥匙“ Alben ”？

我试过了：

$returnArray = array_values($returnArray);

Answer 1

array_values将返回仅包含值的数组，并破坏关联。 您可能需要使用uasort函数来执行此操作，在这里您可以为值提供自定义排序逻辑并维护索引关联。 从PHP Docs：

此函数使用用户定义的比较函数对数组进行排序，以使数组索引保持与与其关联的数组元素的相关性。

这主要用于对实际元素顺序很重要的关联数组进行排序时。

（从它的推导中得出usort ：）

value_compare_func

如果第一个参数分别小于，等于或大于第二个参数，则比较函数必须返回小于，等于或大于零的整数。

这是您提供的代码的示例：

<?php
// array reproducing
$collection = array(
        "Alben" => array (
                "Sgt._Pepper’s_Lonely_Hearts_Club_Band" => "",
                "Rubber_Soul" => "",
                "Please_Please_Me" => "",
                "Let_It_Be_(Album)" => "",
                "With_the_Beatles" => "",
                "Let_It_Be…_Naked" => "",
                "A_Hard_Day’s_Night_(Album)" => "Rickenbacker_360-12WB_12_String.jpg",
                "Beatles_for_Sale" => "",
                "Help!_(Album)" => "Semaphore_Victor.svg",
                "Magical_Mystery_Tour_(Album)" => "",
                "The_Beatles_(Album)" => "ble_test",
                "Yellow_Submarine" => "",
                "Abbey_Road" => "The_End.jpg",
                "Revolver_(Album)" => "",
                "Anthology_(The_Beatles)" => "",
                "A_Collection_of_Oldies_…_but_Goldies" => "",
                "1_(Album)" => "",
        ));

// callback of sorting, checks if the compared value is not empty then pushes it ahead.
// If not, pull it backwards.
$sortIfFilled = function ($a, $b) {
    return (!$a) ? 1 : -1;
};

// Executing it...
uasort($collection['Alben'], $sortIfFilled);

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

输出：

Array
(
    [Alben] => Array
        (
            [The_Beatles_(Album)] => ble_test
            [Abbey_Road] => The_End.jpg
            [A_Hard_Day’s_Night_(Album)] => Rickenbacker_360-12WB_12_String.jpg
            [Help!_(Album)] => Semaphore_Victor.svg
            [Yellow_Submarine] => 
            [Let_It_Be…_Naked] => 
            [A_Collection_of_Oldies_…_but_Goldies] => 
            [Let_It_Be_(Album)] => 
            [Revolver_(Album)] => 
            [Beatles_for_Sale] => 
            [With_the_Beatles] => 
            [Sgt._Pepper’s_Lonely_Hearts_Club_Band] => 
            [Rubber_Soul] => 
            [Magical_Mystery_Tour_(Album)] => 
            [Anthology_(The_Beatles)] => 
            [Please_Please_Me] => 
            [1_(Album)] => 
        )

)

请仔细阅读PHP Docs上的回调函数，它们可能会帮助您解决项目中的类似问题。