Calculating Time Differences

问题

I tried using DateTime in PHP and used diff method to find the time difference between a timestamp and the current time. However PHP gives me the wrong difference. Can anyone point out to me what went wrong in my code? Thanks!

PHP Code

function time() {
    $now = new DateTime;
    $later = new DateTime('2011-10-17 07:08:00');
    $interval = $now->diff($later);
    echo $now->format('y m d');
    echo "<br>";
    echo $later->format('y m d');
    echo "<br>";
    echo $interval->format('%a');
}

Output

11 10 19
11 10 17
6015

The difference is obviously 2 days, but I get 6015 days!

回答1:

You are doing $now->diff($now);, should be $now->diff($later).

回答2:

as written, the result should be 0, because you are doing $now->diff($now)

If you do $later->diff($now) you should get the expected result.

来源：https://stackoverflow.com/questions/7816650/calculating-time-differences