如何在数组中找到最大值和最小值以及相应的日期 - How to find maximaum and minium value in array and also corresponding dates

How to find maximaum and minium value in array and also corresponding dates

我有一个数组，我想要一些输出

Array
    (
[0] => Array
    (
        [DaySession1] => 
        [DaySession] => 
        [SubmitSessionDate] => 
        [id] => 
    )
[1] => Array
    (
        [DaySession2] => 
        [DaySession] => 
        [SubmitSessionDate] => 
        [id] => 
    )
[2] => Array
    (
        [DaySession3] => 2
        [DaySession] => 2
        [SubmitSessionDate] => 2014-09-03 23:58:56
        [id] => 2120
    )
[3] => Array
    (
        [DaySession4] => 10
        [DaySession] => 10
        [SubmitSessionDate] => 2014-09-04 00:06:39
        [id] => 2121
    )
[4] => Array
    (
        [DaySession5] => 
        [DaySession] => 
        [SubmitSessionDate] => 
        [id] => 
    )
[5] => Array
    (
        [DaySession6] => 
        [DaySession] => 
        [SubmitSessionDate] => 
        [id] => 
    )
[6] => Array
    (
        [DaySession7] => 6
        [DaySession] => 6
        [SubmitSessionDate] =>  2014-09-05 00:06:39
        [id] => 
    )

这是我即将到来的数组，我想要上面数组中的最大[DaySession]值，也想要相应的[SubmitSessionDate]

同样，我也想要上面数组中的最小[DaySession]值和相应的[SubmitSessionDate]？

结果应该是：

Maximum Day session = 10 and SubmitSessionDate = 2014-09-04 00:06:39
Minimum Day Session =2  and SubmitSessionDate = 2014-09-03 23:58:56

您只需获得当天会话及其密钥，然后ksort即可使用reset()和end()。示例：演示

$keys = array();
foreach($array as $key => $val) {
    if(!empty($val['DaySession'])) {
        $keys[$val['DaySession']] = $key;
    }
}
ksort($keys);
$min_key = reset($keys);
$max_key = end($keys);
echo "Maximum Day session = ".$array[$max_key]['DaySession']." and SubmitSessionDate = ".$array[$max_key]['SubmitSessionDate']." <br/>";
echo "Minimum Day session = ".$array[$min_key]['DaySession']." and SubmitSessionDate = ".$array[$min_key]['SubmitSessionDate'];