strtotime - php get microtime from date string

Question

I am trying to get the time passed between two datetime strings (including milliseconds)

example:

$pageTime = strtotime("2012-04-23T16:08:14.9-05:00");
$rowTime = strtotime("2012-04-23T16:08:16.1-05:00");
$timePassed = $rowTime - $pageTime;
echo $timePassed . "<br/><br/>";

What I want to see echoed is "1.2" but strtotime() ignores the millisecond part of the string. Also, apparently microtime() doesn't let you give it a datestring... Is there an alternative function for calculating this, or am I going to have to do some string parsing to extract the seconds and milliseconds and subtract?

Answer 1

Try it with DateTime instead.

This needs a bit of a workaround because DateInterval (which is returned by DateTime::diff()) doesn't calculate the microseconds, so you need to this by hand

$pageTime = new DateTime("2012-04-23T16:08:14.1 - 5 hours");
$rowTime  = new DateTime("2012-04-23T16:08:16.9 - 5 hours");

// the difference through one million to get micro seconds
$uDiff = abs($pageTime->format('u')-$rowTime->format('u')) / (1000 * 1000);

$diff = $pageTime->diff($rowTime);

echo $diff->format('%s')-$uDiff;

I always recommend DateTime because of its flexibility, you should look into it

EDIT

For backwards compability to PHP 5.2 it takes the same approach as for the milliseconds:

$pageTime = new DateTime("2012-04-23T16:08:14.1 - 5 hours");
$rowTime  = new DateTime("2012-04-23T16:08:16.9 - 5 hours");

// the difference through one million to get micro seconds
$uDiff = abs($pageTime->format('u')-$rowTime->format('u')) / (1000 * 1000);


$pageTimeSeconds = $pageTime->format('s');
$rowTimeSeconds  = $rowTime->format('s');

if ($pageTimeSeconds + $rowTimeSeconds > 60) {
  $sDiff = ($rowTimeSeconds + $pageTimeSeconds)-60;
} else {
  $sDiff = $pageTimeSeconds - $rowTimeSeconds;
}


if ($sDiff < 0) {
  echo abs($sDiff) + $uDiff;
} else {
  // for the edge(?) case if $dt2 was smaller than $dt
  echo abs($sDiff - $uDiff);
}