给定这个数组:

$inventory = array(

   array("type"=>"fruit", "price"=>3.50),
   array("type"=>"milk", "price"=>2.90),
   array("type"=>"pork", "price"=>5.43),

);

我想按价格排序$inventory的元素,以获得:

$inventory = array(

   array("type"=>"pork", "price"=>5.43),
   array("type"=>"fruit", "price"=>3.50),
   array("type"=>"milk", "price"=>2.90),

);

我该怎么做呢?


当前回答

从PHP 7.4开始,你可以使用arrow函数:

usort(
    $inventory, 
    fn(array $a, array $b): int => $b['price'] <=> $a['price']
);

代码(演示):

$inventory = [
    ['type' => 'fruit', 'price' => 3.50],
    ['type' => 'milk',  'price' => 2.90],
    ['type' => 'pork',  'price' => 5.43],
];

usort(
    $inventory, 
    fn(array $a, array $b): int => $b['price'] <=> $a['price']
);

print_r($inventory);

(浓缩)输出:

Array
(
    [0] => Array ([type] => pork,  [price] => 5.43)
    [1] => Array ([type] => fruit, [price] => 3.5)
    [2] => Array ([type] => milk,  [price] => 2.9)
)

其他回答

这是我很久以前发现的一个方法,并进行了一些清理。这工作得很好,并且可以快速更改为接受对象。

/**
 * A method for sorting arrays by a certain key:value.
 * SortByKey is the key you wish to sort by
 * Direction can be ASC or DESC.
 *
 * @param $array
 * @param $sortByKey
 * @param $sortDirection
 * @return array
 */
private function sortArray($array, $sortByKey, $sortDirection) {

    $sortArray = array();
    $tempArray = array();

    foreach ( $array as $key => $value ) {
        $tempArray[] = strtolower( $value[ $sortByKey ] );
    }

    if($sortDirection=='ASC'){ asort($tempArray ); }
        else{ arsort($tempArray ); }

    foreach ( $tempArray as $key => $temp ){
        $sortArray[] = $array[ $key ];
    }

    return $sortArray;

}

要更改排序对象的方法,只需更改以下行:

$tempArray[] = strtolower($value[$sortByKey]); 来 $tempArray[] = strtolower($value->$sortByKey);

要运行该方法,只需执行

盘存、’price’’ASC’sortArray(美元);

试试这个:

$prices = array_column($inventory, 'price');
array_multisort($prices, SORT_DESC, $inventory);
print_r($inventory);

因为数组元素本身就是带有字符串键的数组,所以最好定义一个自定义比较函数。做起来又快又简单。试试这个:

function invenDescSort($item1,$item2)
{
    if ($item1['price'] == $item2['price']) return 0;
    return ($item1['price'] < $item2['price']) ? 1 : -1;
}
usort($inventory,'invenDescSort');
print_r($inventory);

产生以下结果:

Array
(
    [0] => Array
        (
            [type] => pork
            [price] => 5.43
        )

    [1] => Array
        (
            [type] => fruit
            [price] => 3.5
        )

    [2] => Array
        (
            [type] => milk
            [price] => 2.9
        )

)

许多人都在寻找一种方法来做Laravel,并最终在这里结束。此外,一些Laravel问题由于这个问题的重复而被关闭。 因此,我分享了一种使用Laravel collect()方法执行它的简单方法。

$inventory = collect($inventory)->sortBy('price')->toArray();

降序排列

$inventory = collect($inventory)->sortBy('price')->reverse()->toArray();

Or,

$inventory = collect($inventory)->('price')->reverse()->toArray();

我是这样用的

<?php
$users = [
    [
        'username' => 'joe',
        'age' => 11
    ],
    [
        'username' => 'rakoto',
        'age' => 21
    ],
    [
        'username' => 'rabe',
        'age' => 17
    ],
    [
        'username' => 'fy',
        'age' => 19
    ],    
];


uasort($users, function ($item, $compare) {
    return $item['username'] >= $compare['username']; 
});

var_dump($users);