time remainig

[omerbutt]

hi
i have an application for online test i have to show the time remainig and update it accordingly and show that how much time is left for the paper
the admin gives the time limit in minutes
say he gives 60 minutes for the paper now when the paper starts it should shw the remaining time ,i have been pulling my hairs from hours and could not get it done , i am convertinng the current time to seconds the take the allowed mionutes and convert them to seconds and then add it up into the resultant of the current time this way i can get the futer time limit when the test is over but i want to show the time remaining in minutes like 59mins left 58 mins left i just want any one to help me out

$time=date("h:i:s");
$t=split(":",$time);
$a=$t[0]*60;
$st=$a+$t[1];
$st=$st*60;
$st=$st+$a[2];
$given_time_seconds=60*60;
$limit=$st+$given_time_seconds;
$remaining_time=$limit-$st;

[Dormilich]

you mean something like

<?php
define('ALLOWED_TIME_MIN', 60);
$a = new DateTime('2009-08-08 14:07:23'); // start time (needs to be set)
$b = new DateTime(); // current time (variable)

echo ALLOWED_TIME_MIN - $a->diff($b)->i; // time difference in minutes
?>

[omerbutt]

you mean something like

<?php
define('ALLOWED_TIME_MIN', 60);
$a = new DateTime('2009-08-08 14:07:23'); // start time (needs to be set)
$b = new DateTime(); // current time (variable)

echo ALLOWED_TIME_MIN - $a->diff($b)->i; // time difference in minutes
?>

i aint got any idea about how to do it cause havent done that before but i tried you method and it gave me an error it needs the class i think

Fatal error: Call to undefined method DateTime::diff( ) in F:\xampp\htdocs \sfanProjects\e xamples\jqtime. php on line 85

[Dormilich]

looks like PHP 5.2. (got that same error with my built-in PHP).

it works with PHP 5.3. (though DateTime is supported since 5.2, some methods require 5.3)

if that’s not an option (upgrading) you probably need something along

$remain = ALLOWED_TIME_MIN * 60 - time() + time(strtotime('2009-08-08 14:07:23'));

[omerbutt]

how can i get the server time as it is an online test application and the user can change or reverse the time on his pc to extend the time limit

[Dormilich]

take the time when the test starts and save it in a session. if the user tries to break the session, disqualify him/her.

changing the user machine’s time won’t work, since your script uses your server’s time.

[omerbutt]

means if he intentionally or un-intentionally presses the refresh button the time will not restart and continue from the begining....bec ause i think i was sitting on the same machine where the application was residing and when i changed the time on the clock it changed in the paper too , but i think you are right when the application will be installed at the client end then the user would be sitting on their PC and not the server where the application is residing and changing the time on the users machine wont effect the original PAper Time .............ap art from this .....about how the process flows
i am doing the same thing when the page loads i take the given time say 20 mins and then add those minutes to the current time and mark the limit if lets say currently is 3:10 pm and he is allowed 20mis for the exam i add the minutes and the end time is 3:30 pm and save it into the session variable and then after every minute it makes an ajax calls that subtracts the current time from the end time and calculates the time left , is this alright means is there any thing or check i should be adding
regards,
Omer Aslam

[Dormilich]

is this alright means is there any thing or check i should be adding

there’s currently nothing coming to my mind. you only need to test thoroughly.

[omerbutt]

ok
that's fine
regards,
Omer Aslam