每小时刷新一次内容/页面

Question

I have a code that is meant to refresh the page on the hour, every hour but it doesn't seem to execute...

This is the code:

<?php

date_default_timezone_set('Australia/Sydney');

$date = date("i:s");

list($cur_min, $cur_sec) = explode(':', $date);

$mins_left = ($cur_min == 59) ? 0 : 60 - $cur_min;
$secs_left = 60 - $cur_sec;

$time=($mins_left*60+$secs_left)*1000;

?>

<script type="text/javascript">
setInterval("refresh()",<?php echo $time; ?>);
function refresh(){
    window.location = location.href;
}
</script>

I need it to run off the server clock too and not from when the user lands on the page.

Idealy, would be awesome if it could just refresh the content of every div labeled with the class named "locality"...

Answer 1

Try this code for the JavaScript part:

function refresh(){
    window.location.reload();
}
setTimeout(refresh, <?php echo $time; ?>);

I'm not sure if it will solve your problem, but I tried a few changes:

• window.location.reload() is more explicit than window.location = location.href (which, by the way, could be simplified to window.location = window.location )
• setTimeout instead of setInterval because if the refreshing fails again for some reason, you don't want to try refreshing again in
• put the setTimeout call after the definition of the function to be sure that there isn't a problem with the function not being defined yet

Try it. If that code still doesn't work for you, try looking at your generated HTML and seeing what value for $time was printed. Also check the browser console for any errors.

By the way, the code would be clearer if you renamed the variable $time to $ms_until_start_of_hour .

Answer 2

I would use DateTime in PHP and for easy convertion use timestamps.

$date = new \DateTime(strtotime(time()), new \DateTimeZone("Australia/Sydney")));
$date->add(new \DateInterval('PT1H'));
$time = $date->format('U') % 3600;

And for JS:

var time = (Math.round((new Date()).getTime() / 1000) % 3600);
if(time > <?= $time ?>){
  var rtime = time - <?= $time ?>;
} else {
  var rtime = <?= $time ?> - time; 
}

setInterval(function(){
  window.location.reload(1);
},rtime * 1000);

But im not sure why:

<meta http-equiv="refresh" content="3600">

Will not suffice as it will just refresh an hour later (and so on) of when the user enters the page, doesn't really matter what timezone.