php 二维数组打乱顺序

public function shuffle_assoc($list) {
if (!is_array($list)) return $list;

$keys = array_keys($list);
shuffle($keys);
$random = array();
foreach ($keys as $key)
$random[$key] = $this->shuffle_assoc($list[$key]);
return $random;
}
public function test(){
$data = array(
array("id"=>13,"name"=>"张三"),
array("id"=>1,"name"=>"李爱媛"),
array("id"=>6,"name"=>"蔡依林"),
array("id"=>8,"name"=>"陈思"),
array("id"=>21,"name"=>"何达玲"),
array("id"=>14,"name"=>"赵勇"),
);
$tmp = $this->shuffle_assoc($data);
var_dump($tmp);die;
}
//===============打印结果================

array(6) {
[3]=>
array(2) {
["id"]=>
int(8)
["name"]=>
string(6) "陈思"
}
[5]=>
array(2) {
["id"]=>
int(14)
["name"]=>
string(6) "赵勇"
}
[1]=>
array(2) {
["id"]=>
int(1)
["name"]=>
string(9) "李爱媛"
}
[0]=>
array(2) {
["name"]=>
string(6) "张三"
["id"]=>
int(13)
}
[2]=>
array(2) {
["id"]=>
int(6)
["name"]=>
string(9) "蔡依林"
}
[4]=>
array(2) {
["id"]=>
int(21)
["name"]=>
string(9) "何达玲"
}
}