checking Javascript client side

foid025

I was wondering if there is any way to check if a client has Javascript enabled - using PHP. My hunch is that this is impossible, just because PHP is server side - but perhaps?

Otherwise, do you know of any alternatives? I know that the usual way to go about this is to use a Javascript script to redirect a user if they have Javascript, but I would much rather redirect the ones that do not have Javascript. After all, why waste the time of 90% of users when you can only waste the time of 10%.

Any ideas? Thanks!

Piranha

Please take a look at this thread. If you still have questions afterwards, fire away.

scrupul0us

<?php
//check for JS

echo '<noscript>';
header("location: index.php?js=0");
echo '</noscript>';
?>

madwormer2

Lol, if you seriously think that'll work, you're mistaken.

scrupul0us

i remember it working (or some adaptation of) in the past

scrupul0us

this works nicely tho

<?php
if (isset($_POST['jstest'])) {
  $nojs = FALSE;
  } else {
  // create a hidden form and submit it with javascript
  echo '<form name="jsform" id="jsform" method="post" style="display:none">';
  echo '<input name="jstest" type="text" value="true" />';
  echo '<script language="javascript">';
  echo 'document.jsform.submit();';
  echo '</script>';
  echo '</form>';
  // the variable below would be set only if the form wasn't submitted, hence JS is disabled
  $nojs = TRUE;
}
if ($nojs){
  //JS is OFF, do the PHP stuff
}
?>

madwormer2

Yup, like this:

<noscript><meta http-equiv="refresh" content="0;url=?js=0"></noscript>

scrupul0us

yes thats it madwormer!

dougal85

I don't understand why people need to detect if JavaScript is there or not?

edit

Just had an idea, if you really want to do this and only download files that js users need... (ive not tried this btw, just an idea)


<script blah blah...>

function include(script_filename) {
    document.write('<script language="javascript"  type="text/javascript" src="' + script_filename + '"></script>');
}

include('myamazingjs.js');

</script>

etully

I don't understand why people need to detect if JavaScript is there or not?

Actually, I think it's a fair question. Once upon a time, Javascript sucked and only fools relied on it. Now that it's fairly stable (though I still find cross browser problems), we can make some great improvements in useability.

I hate gimmicks as much as the next guy - and most of Web 2.0 has been stupid gimmicks - but when done right, it makes a site easier to use. There is a CPU at each end (client and server) and there's no reason for the server to do all the work.

But we should be handing one version of the site or another to the user based on whether or not they have JS so there is good reason to want to know.

dougal85

etully wrote:
and most of Web 2.0 has been stupid gimmicks

Man, I totally love lots of the web 2.0 stuff. event the pointless experimental stuff. although, there are some websites that are just really bad. the new hot mail for example, i hate it. its so slow.

etully wrote:
But we should be handing one version of the site or another to the user based on whether or not they have JS so there is good reason to want to know.

I'd much rather programming JavaScript so it degrades well, rather than attempting to do two versions of the website. what happens if somebody without JavaScript gets a link to the version with JavaScript enabled in the url? sounds like allot of hassle.

bradgrafelman

dougal85 wrote:
what happens if somebody without JavaScript gets a link to the version with JavaScript enabled in the url?

Generate your entire site via document.write()'s? :p

dougal85

Yeah, I've got a js file for each page.... with functions it reduces the page code HUGELY! Shame the js file is 5mb

index.html becomes...

<script type="text/javascript">

myusefulsitefunctions.printPageFull();

</script>

:p :p :p