每 30 秒自动刷新页面

Question

I have a JSP page which has to display the status of various jobs that are running. Some of these jobs take time, so it takes a while for their status to change from processing to complete.

Is it a good idea to have a javascript function that would refresh the page every 30 seconds or so? Are there any ramifications for having a script that is constantly refreshing a page?

The other option is to have a refresh button which on click would refresh the page.

Answer 1

There are multiple solutions for this. If you want the page to be refreshed you actually don't need JavaScript, the browser can do it for you if you add this meta tag in your head tag.

<meta http-equiv="refresh" content="30">

The browser will then refresh the page every 30 seconds.

If you really want to do it with JavaScript, then you can refresh the page every 30 seconds with Location.reload() ( docs ) inside a setTimeout() :

window.setTimeout(function () {
  window.location.reload();
}, 30000);

If you don't need to refresh the whole page but only a part of it, I guess an AJAX call would be the most efficient way.

Answer 2

Just a simple line of code in the head section can refresh the page

<meta http-equiv="refresh" content="30">

although its not a javascript function, its the simplest way to accomplish the above task hopefully.

Answer 3

Use setInterval instead of setTimeout . Though in this case either will be fine but setTimeout inherently triggers only once setInterval continues indefinitely.

<script language="javascript">
setInterval(function(){
   window.location.reload(1);
}, 30000);
</script>

Answer 4

If you want refresh the page you could use like this, but refreshing the page is usually not the best method, it better to try just update the content that you need to be updated.

javascript:

<script language="javascript">
setTimeout(function(){
   window.location.reload(1);
}, 30000);
</script>