Countdown timer Ajax and PHP

[v0idmp3]

Hi

 

I have a little problem. I develop browser game and I dont know how to build countdown timer. For example...When player click on "Build Something", I need to show him a countdown timer, from start time to some time in future, and countdown difference from start and end time. And than, when timer reach zero, I need to put some data in database. I think a lot about that, and I realized that I must have in my database start and end time, but I dont know how to calculate remaing time when player logout from game, and than log in again. How to show him how much time was spend when he was offline? If you know some tutorial about Ajax/JS countdown timers, I will be very thankful. I searched google, but I didnt find what I need. I'm new to ajax/js and I really dont know how to make that.

 

Cheers

[smoseley]

var timeLeft = 300; // 5 minutes
var timer = window.setInterval(function() {
    timeLeft--;
    var minutesLeft = Math.floor(timeLeft / 60);
    var secondsLeft = timeLeft % 60;
    console.log('Time left: ' + minutesLeft + ':' + secondsLeft);
    if (timeLeft == 0) {
        window.clearInterval(timer);
        // do some ajax thing
    }
}, 1000);

[v0idmp3]

Ok, thanks for code...But I need to pass variable "timeLeft" from PHP. How to do that?

[smoseley]

If my snippet didn't fully answer your "little problem" (and then some), I'm afraid you don't have enough knowledge to build the game you want to make. 

 

I suggest you buy books on PHP & Javascript and do some reading.

 

Cheers!

[smoseley]

By the way here's the answer to your last question:

 

<?php
// Some code
$timeLeft = 300;
?>
<script type="text/javascript">
var timeLeft = <?=$timeLeft?>; // 5 minutes
var timer = window.setInterval(function() {
    timeLeft--;
    var minutesLeft = Math.floor(timeLeft / 60);
    var secondsLeft = timeLeft % 60;
    console.log('Time left: ' + minutesLeft + ':' + secondsLeft);
    if (timeLeft == 0) {
        window.clearInterval(timer);
        // do some ajax thing
    }
}, 1000);
</script>

 

But of course, your next question will be...

[v0idmp3]

Hm...When I try to use your code, it's doesn't work? I simply have white page, and nothing on it.

 

Can you recommend me some book about PHP and JS?

[smoseley]

I can't recommend a book.  Look on Amazon for highly rated books.

 

My code is logging to the console.  If you hit F12 in a console-enabled browser, and click the console tab, you'll see the output.

[Mahngiel]

Likely his .ini isn't set to use short-tags.  He'll need to either enable that, or use

var timeleft = <?php echo$timeleft; ?>;

[smoseley]

Likely his .ini isn't set to use short-tags.  He'll need to either enable that, or use

var timeleft = <?php echo $timeleft; ?>;

Likely not  That's very rare.  Likely the issue is he just doesn't understand how JS console works.