<?php

$utcdatetime = new MongoDB\BSON\UTCDateTime(1416445411987);

$datetime = $utcdatetime->toDateTime();

var_dump($datetime->format('r'));

var_dump($datetime->format('U.u'));

var_dump($datetime->getTimezone());

?>

//convert retrieved time back to local time

<?php

/********************constructor**********************************/

$orig_date = new DateTime('2016-06-27 13:03:33');

$orig_date=$orig_date->getTimestamp();

$utcdatetime = new MongoDB\BSON\UTCDateTime($orig_date*1000);

/********************retrieve time in UTC**********************************/

$datetime = $utcdatetime->toDateTime();

$time=$datetime->format(DATE_RSS);

/********************Convert time local timezone*******************/

$dateInUTC=$time;

$time = strtotime($dateInUTC.' UTC');

$dateInLocal = date("Y-m-d H:i:s", $time);

echo $dateInLocal;

?>

output: 2016-06-27 13:03:33

$tz = new DateTimeZone('Asia/Kolkata'); //Change your timezone

$date = date("Y-m-d h:i:sa"); //Current Date

$a = new MongoDB\BSON\UTCDateTime(strtotime($date)*1000);

      $datetime = $a->toDateTime();

      echo '<pre>';print_r($datetime);echo '</pre>';

      $datetime->setTimezone($tz); //Set timezone

      $time=$datetime->format(DATE_ATOM);  //(example: 2005-08-15T15:52:01+00:00)

    echo "<br>". $time . "<br>";

OUTPUT :

//Output of datetime object

DateTime Object

(

    [date] => 2016-08-09 14:57:06.000000

    [timezone_type] => 1

    [timezone] => +00:00

)

//Output of time

2016-08-09T20:27:06+05:30