PHP 二维数组根据某个字段排序 复制代码 array_multisort

//二维数组，按照里面的age从大到小降序，代码如下

<?php
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,),
);

$arrSort = array();
foreach($arrUsers as $uniqid => $row){
    foreach($row as $key=>$value){
        $arrSort[$key][$uniqid] = $value;
    }
}
//$arrSort 为
// array(
//   "id"=>array(1,2,3,4,5),
//   "name"=>array("张三","李四","王五","赵六","黄七"),
//   "age"=>array(25,23,40,31,20)
// );

//array_multisort(排序字段，倒序/顺序，数组)
array_multisort($arrSort['age'], constant('SORT_DESC'), $arrUsers);

echo '<pre>';
var_dump($arrUsers);

/*
输出结果：

array(5) {
  [0]=>
  array(3) {
    ["id"]=>
    int(3)
    ["name"]=>
    string(6) "王五"
    ["age"]=>
    int(40)
  }
  [1]=>
  array(3) {
    ["id"]=>
    int(4)
    ["name"]=>
    string(6) "赵六"
    ["age"]=>
    int(31)
  }
  [2]=>
  array(3) {
    ["id"]=>
    int(1)
    ["name"]=>
    string(6) "张三"
    ["age"]=>
    int(25)
  }
  [3]=>
  array(3) {
    ["id"]=>
    int(2)
    ["name"]=>
    string(6) "李四"
    ["age"]=>
    int(23)
  }
  [4]=>
  array(3) {
    ["id"]=>
    int(5)
    ["name"]=>
    string(6) "黄七"
    ["age"]=>
    int(20)
  }
}

*/