php DateTime to ISO-8601 time code example

Example 1: php convert date and time to iso 8601

//Object Oriented Method

$datetime = new DateTime('2010-12-30 23:21:46');

echo $datetime->format(DateTime::ATOM); // Updated ISO8601


//Procedural Method

echo date(DATE_ISO8601, strtotime('2010-12-30 23:21:46'));

Example 2: ISO 8601 php

FYI: there's a list of constants with predefined formats on the DateTime object, for example instead of outputting ISO 8601 dates with:

<?php
echo date('c');
?>

or

<?php
echo date('Y-m-d\TH:i:sO');
?>

You can use

<?php
echo date(DateTime::ISO8601);
?>

instead, which is much easier to read.