PHP 二维数组根据某个字段排序

<?php /** * 二维数组根据某个字段排序 * 功能：按照用户的年龄倒序排序 * @author ruxing.li */header('Content-Type:text/html;Charset=utf-8');$arrUsers = array(    array(            'id'   => 1,            'name' => '张三',            'age'  => 25,    ),    array(            'id'   => 2,            'name' => '李四',            'age'  => 23,    ),    array(            'id'   => 3,            'name' => '王五',            'age'  => 40,    ),    array(            'id'   => 4,            'name' => '赵六',            'age'  => 31,    ),    array(            'id'   => 5,            'name' => '黄七',            'age'  => 20,    ),); $sort = array(        'direction' => 'SORT_DESC', //排序顺序标志 SORT_DESC 降序；SORT_ASC 升序        'field'     => 'age',       //排序字段);$arrSort = array();foreach($arrUsers AS $uniqid => $row){    foreach($row AS $key=>$value){        $arrSort[$key][$uniqid] = $value;    }}if($sort['direction']){    array_multisort($arrSort[$sort['field']], constant($sort['direction']), $arrUsers);}var_dump($arrUsers);/*输出结果：array (size=5)  0 =>     array (size=3)      'id' => int 5      'name' => string '黄七' (length=6)      'age' => int 20  1 =>     array (size=3)      'id' => int 2      'name' => string '李四' (length=6)      'age' => int 23  2 =>     array (size=3)      'id' => int 1      'name' => string '张三' (length=6)      'age' => int 25  3 =>     array (size=3)      'id' => int 4      'name' => string '赵六' (length=6)      'age' => int 31  4 =>     array (size=3)      'id' => int 3      'name' => string '王五' (length=6)      'age' => int 40*/