我有一个复杂的多维数组。结构类似于
Array
(
[0] => Array
(
[countries] => Array
(
[0] => Array
(
[country_code] => US
[growth] => 3.57
)
[1] => Array
(
[country_code] => CA
[growth] => 4.77
)
[2] => Array
(
[country_code] => TT
[growth] => 0
)
)
[group_name] => North America
)
[1] => Array
(
[countries] => Array
(
[0] => Array
(
[country_code] => BR
[growth] => 2.19
)
[1] => Array
(
[country_code] => PE
[growth] => 1.78
)
[2] => Array
(
[country_code] => UY
[growth] => 8.83
)
[3] => Array
(
[country_code] => MX
[growth] => 3.83
)
)
[group_name] => South America
)
)
我想对它们进行排序（可以使用array_multisort），以便根据growth（最高优先）进行排序
这样排序后的数组将是
Array
(
[0] => Array
(
[countries] => Array
(
[0] => Array
(
[country_code] => CA
[growth] => 4.77
)
[1] => Array
(
[country_code] => US
[growth] => 3.57
)
[2] => Array
(
[country_code] => TT
[growth] => 0
)
)
[group_name] => North America
)
[1] => Array
(
[countries] => Array
(
[0] => Array
(
[country_code] => UY
[growth] => 8.83
)
[1] => Array
(
[country_code] => MX
[growth] => 3.83
)
[2] => Array
(
[country_code] => BR
[growth] => 2.19
)
[3] => Array
(
[country_code] => PE
[growth] => 1.78
)
)
[group_name] => South America
)
)
我是PHP的新手，所以我不知道如何对这个复杂的数组进行排序。我知道如何对siimple多维数组进行排序，如中所示http://in2.php.net/manual/en/function.array-multisort.php
最坏的情况是，您创建自己的排序函数并使用usort
它实际上是为这类事情而设计的。
在您的情况下，您将传递$arr[$i]['countries']，并使比较函数基于$arr['growth']进行排序。
多年来，我一直在使用以下排序功能：
/**
* sorting array of associative arrays - multiple row sorting using a closure
* see also: the-art-of-web.com/php/sortarray/
* @param array $data input-array
* @param string|array $fields array-keys
* @license Public Domain
* @return array
*/
function sortArray( $data, $field )
{
$field = (array) $field;
uasort( $data, function($a, $b) use($field) {
$retval = 0;
foreach( $field as $fieldname )
{
if( $retval == 0 ) $retval = strnatcmp( $a[$fieldname], $b[$fieldname] );
}
return $retval;
} );
return $data;
}
// example call, sort by 'growth' first and by 'country_code' afterwards
// this would be equal to a MySQL 'ORDER BY `growth` ASC, `country_code` ASC'
foreach( $countryArray as &$item )
{
$item['countries'] = sortArray( $item['countries'], array( 'growth', 'country_code' ) );
}