PHP DateTime microseconds always returns 0

Question

this code always returns 0 in PHP 5.2.5 for microseconds:

format(\"Y-m-d\\TH:i:s.u\") . \"\\n\";
?>
         


        

Answer 1

Some answers make use of several timestamps, which is conceptually wrong, and overlapping issues may occur: seconds from 21:15:05.999 combined by microseconds from 21:15:06.000 give 21:15:05.000.

Apparently the simplest is to use DateTime::createFromFormat() with U.u, but as stated in a comment, it fails if there are no microseconds.

So, I'm suggesting this code:

function udate($format, $time = null) {

    if (!$time) {
        $time = microtime(true);
    }

    // Avoid missing dot on full seconds: (string)42 and (string)42.000000 give '42'
    $time = number_format($time, 6, '.', '');

    return DateTime::createFromFormat('U.u', $time)->format($format);
}