如何添加11小时的时间存储为字符串

I have a date and timestamp in HL7 format : 201402181659

That represents 2014 02 18 at 16:59

it's offset by +11:00 hours so I need to be able to add 11 hours to the date/time. Any ideas?

You can use DateTime::createFromFormat() to parse the string and then DateTime::modify() to add 11 hours to it:

$date = DateTime::createFromFormat('YmdHis', '201402181659');
$date->modify('+11 hours');
echo $date->format('YmdHis');

You can also use DateTime::add() with DateInterval() to add the 11 hours:

$date = DateTime::createFromFormat('YmdHis', '201402181659');
$date->add(new DateInterval('PT11H'));
echo $date->format('YmdHis');