Question

I have a unix time eg: var later= 135000;

When I take the variable later -= 1000 I am able to get 134000.

But when I take the variable later += 1000 I get 1350001000.

How can I increase my unix time?

<script type="text/javascript"> 
   var later = "<?php echo $unix_time; ?>";
   var stop= setInterval('countdown()',1000);

   function countdown(plus_ten) {
        var now = new Date();

        var now_time= now.getTime()/1000;
        now_time= Math.floor(now_time);

        if(plus_ten){
            later = later + 1000;
            alert(later);
        }

        var sec = later- now_time;
        if(sec<=0){
            clearInterval(stop);
            alert('hello');
        }

        sec= Math.floor(sec);
        var min = Math.floor(sec / 60);
        var hour = Math.floor(min / 60);

        hour %= 24;
        min %= 60;
        sec %= 60;

        document.getElementById("hoursBox").innerHTML = hour;
        document.getElementById("minsBox").innerHTML = min;
        document.getElementById("secsBox").innerHTML = sec;       
    }
</script>

Answer 1

Your variable ‘later’ is assigned a string value when you do:

var later = "<?php echo $unix_time; ?>";

You should instead do:

var later = <?php echo $unix_time; ?>; // i.e. no quotes around the time stamp

That should fix it.