TimeAgo函数返回负秒

Question

I have a function that returns how long ago the time was posted, but there seem be to a slight problem with it. The first time, $timeAgo1 works just fine, but the second time, $timeAgo2 seems to return negative seconds. How is that happening?

<?php

//*****************************************************START OF FUNCTION
function timeAgo($time_ago) {

    $time_ago = strtotime($time_ago);
    $cur_time = time();
    $time_elapsed = $cur_time - $time_ago;
    $seconds = $time_elapsed ;
    $minutes = round($time_elapsed / 60 );
    $hours = round($time_elapsed / 3600);
    $days = round($time_elapsed / 86400 );
    $weeks = round($time_elapsed / 604800);
    $months = round($time_elapsed / 2600640 );
    $years = round($time_elapsed / 31207680 );

    echo $seconds."<br>";
    if ($seconds <= 60) {
        return "just now";
    } //end of if ($seconds <= 60)

    else if ($minutes <=60) {
        if ($minutes == 1) {
            return "one minute ago";
        } //end of else if ($minutes <=60)
        else {
            return "$minutes minutes ago";
        } //end of else not ($minutes == 1)
    } //end of else if ($minutes <= 60)


    else if ($hours <= 24) {
        if ($hours == 1) {
            return "an hour ago";
        } //end of if ($hours == 1)
        else {
            return "$hours hours ago";
        } //end of else not ($hours == 1)
    } //end of else if ($hours <= 24)


    else if ($days <= 7) {
        if ($days == 1) {
            return "yesterday";
        } //end of else if ($days <= 7)
        else {
            return "$days days ago";
        } //end of else not ($days == 1)
    } //end of else if ($days <= 7)

    else if ($weeks <= 4.3) {
        if ($weeks == 1) {
            return "a week ago";
        } //end of if ($weeks == 1)
        else {
            return "$weeks weeks ago";
        } //end of else not ($weeks == 1)
    } //end of else if ($weeks <= 4.3)


    else if ($months <= 12) {
        if ($months == 1) {
            return "a month ago";
        } //end of if ($months == 1)
        else {
            return "$months months ago";
        } //end of else not ($months == 1)
    } //end of else if ($months <= 12)

    else {
        if ($years == 1) {
            return "one year ago";
        } //end of if ($years == 1)
        else {
            return "$years years ago";
        } //end of else not ($years == 1)
    } //end of last else

} //end of function timeAgo($time_ago)
//*****************************************************END OF FUNCTION

$date1 = "2016-02-10";
$time1 = "22:41:58";
$date2 = "2016-02-12";
$time2 = "15:25:57";

$timeAgo1 = timeAgo($date1.$time1);
$timeAgo2 = timeAgo($date2.$time2);

echo $timeAgo1."<br>".$timeAgo2;

?>

Answer 1

Set the timezone in the beginning of the script to the same date as original dates you are checking against, example:

date_default_timezone_set('America/Los_Angeles');

http://php.net/manual/en/function.date-default-timezone-set.php