根据特定列对 php 中的多维数组进行排序

Question

我想根据内部数组中的字段对多维数组进行排序，如下所示：

$result = array(
  array("first" => 1, "second" => 5),
  array("first" => 3, "second" => 8),
  array("first" => 6, "second" => 7),
  array("first" => 6, "second" => 1)
);

sort($result,"second");

/*
$result = array(
  array("first" => 6, "second" => 1),
  array("first" => 1, "second" => 5),
  array("first" => 6, "second" => 7),
  array("first" => 3, "second" => 8)
);
*/

PHP 中是否有类似预期排序功能的东西，或者我是否必须重新实现它？

Answer 1

为此使用usort

This function will sort an array by its values using a user-supplied comparison function. If the array you wish to sort needs to be sorted by some non-trivial criteria, you should use this function.

function cmp($a, $b) {
    if ($a['second'] == $b['second']) {
        return 0;
    }
    return ($a['second'] < $b['second']) ? -1 : 1;
}
usort($array, 'cmp');

您甚至可以先排序 'second'，然后排序 'first' :)（如果 'second' 相同，则排序 'first'）

function cmp($a, $b) {
    if ($a['second'] == $b['second']) {
        if ($a['first'] == $b['first']) {
            return 0;
        }
        return ($a['first'] < $b['first']) ? -1 : 1;
    }
    return ($a['second'] < $b['second']) ? -1 : 1;
}
usort($array, "cmp");

Answer 2

这是一个非常简单的数组排序函数。

function sort_by_key($a, $subkey) {
    foreach($a as $k=>$v) {
        $b[$k] = strtolower($v[$subkey]);
    }
    asort($b);
    foreach($b as $key=>$val) {
        $c[] = $a[$key];
    }
    return $c;
}

你可以这样称呼它：

sort_by_key($result , 'second');

根据特定列对 php 中的多维数组进行排序

sort mulitdimensional array in php according to specific column

php

sorting

multidimensional-array