PHP：关联数组中的下一个值

Question

我有两个关联数组$jar_array和$julla_array。

我像这样遍历他们

foreach ($jar_array as $k => $v) {
    foreach ($v as $ke => $vl) {
        print_r($vl);
        print_r($julla_array[$k][$ke]);
        print_r(next($julla_array[$k][$ke]));//this doesn't work
        exit;
    }
}

问题是：next()函数不会返回$julla_array中的下一个值。我在这里做什么错了？

我尝试添加这样的引用

foreach($jar_array as $k => &$v){

foreach($v as $ke => &$vl){
    print_r($vl);
    print_r($julla_array[$k][$ke]);
    print_r(next($julla_array[$k][$ke]));
    exit;
   }
}

这也无济于事。

$jar_array内容如下

    Array
(
    [2667] => Array
        (
            [2017-10-13] => Array
            (
                [0] => 2147831419
                [jar_id] => 2147831419
                [1] => 2667
                [jar_userid] => 2667
                [2] => 2017-10-13
                [jar_date] => 2017-10-13

             )

        )

   )

$julla_array内容如下

    Array
(
    [2667] => Array
         (
             [2017-10-13] => Array
                (
                [0] => 5380097
                [julla_id] => 5380097
                [1] => 2017-10-13 18:00:41
                [julla_date] => 2017-10-13 18:00:41
                [2] => 2667
                [julla_userid] => 2667
                [3] => 112
                [julla_shift] => 112
                [4] => 2
                [julla_action] => 2
                [5] => 2017-10-13
                [n_julla_date] => 2017-10-13
               ) 
         )
    )