Timestamp older than current time if else statement - php

Question

Im testing an online/offline function with timestamp from the database against DateTime NOW.
But I cant figure out how to set interval time on lets say 5 minutes.
If the user has not done anything in 5 minutes, appear offline.
DateTime NOW will always be bigger than Database time.
Any ideas on how to set the interval time on the statement ?
This is what i have so far,
// $user_info['activity'] 2013-04-27 19:27:39 //
$dateTime = new DateTime("now", new DateTimeZone('Europe/Warsaw'));
if($user_info['activity']>$dateTime){
echo 'user Online';
}else{
echo 'user inactive';
}

Answer 1

Something liKe this might work
$now = new DateTime(null, new DateTimeZone('Europe/Warsaw'));
$last_activity = new DateTime($user_info['activity']);
$last_activity->modify('+5 minutes');
if($now > $last_activity){
echo 'user inactive';
}else{
echo 'user online';
}

Answer 2

Use DateTime::diff() for this:
$now = new DateTime();
$activity = $user_info['activity'];
// get difference between the two dates
$difference = $now->diff($activity);
// ->i contains the minutes
if($difference->i >= 5) {
echo "logged out";
}

Answer 3

One possible solution is to change your database timestamp to be a DateTime object as well and then use the DateTime::diff() method for comparison.
$dateTime1 = new DateTime(strtotime($user_info['activity']), new DateTimeZone('Europe/Warsaw'));
$dateTime2 = new DateTime("now", new DateTimeZone('Europe/Warsaw'));
$interval = $dateTime1->diff($dateTime2);
This will allow you to determine the interval and do a comparison using it.

Answer 4

I did this recently, like this:
$time = time();
$last_activity = //time from db
$time_since = $time - $last_activity
Then clean up $time_since if necessary for your application.