JS File Caching

[Attila]

Hello,

My website stores JavaScript in .js files. From what I understand,
most web browsers cache .js files. My question is, if I make changes
to the file, how can I be sure that users will use the most recent
version of the JS file?

Thanks,
Attila

[Michael Winter]

Re: JS File Caching

On 16 Jan 2004 07:33:19 -0800, Attila <ThisIsAFakeAdd ress35@hotmail. com>
wrote:
[color=blue]
> My website stores JavaScript in .js files. From what I understand,
> most web browsers cache .js files. My question is, if I make changes
> to the file, how can I be sure that users will use the most recent
> version of the JS file?[/color]

Cache management with .js files (any file, really) should work the same as
it does with .htm(l) files. If it doesn't you have a bad browser.

Mike

--
Michael Winter
M.Winter@blueyo nder.co.invalid (replace ".invalid" with ".uk" to reply)

[Dr John Stockton]

Re: JS File Caching

JRS: In article <9516751f.04011 60733.4da55fb@p osting.google.c om>, seen
in news:comp.lang. javascript, Attila <ThisIsAFakeAdd ress35@hotmail. com>
posted at Fri, 16 Jan 2004 07:33:19 :-
[color=blue]
> My website stores JavaScript in .js files. From what I understand,
>most web browsers cache .js files. My question is, if I make changes
>to the file, how can I be sure that users will use the most recent
>version of the JS file?[/color]

Untested :

every page has

<script type="text/javascript">

document.write(
'<script type="text/javascript" src="version.js ?' +
new Date() + '"></scr'+'ipt>'
)

</script>

version.js is thus effectively uncached.

File version.js contains ONLY

var LatestVersion = 99 // update number as needed


Other pages contain, after as above,

<script type="text/javascript">

document.write(
'<script type="text/javascript" src="page45.js? ' +
LatestVersion + '"></scr'+'ipt>'
)

</script>


ISTR that script can write script blocks, but the </script> must be
concealed.

Now, changing the contents of version.js effectively invalidates all
caches, although it does not flush the old stuff. ???

Naturally, you can have an array for LatestVersion, to control cacheing
of different groups of pages independently.

/Untested.

--
© John Stockton, Surrey, UK. ?@merlyn.demon. co.uk Turnpike v4.00 IE 4 ©
<URL:http://jibbering.com/faq/> Jim Ley's FAQ for news:comp.lang. javascript
<URL:http://www.merlyn.demo n.co.uk/js-index.htm> jscr maths, dates, sources.
<URL:http://www.merlyn.demo n.co.uk/> TP/BP/Delphi/jscr/&c, FAQ items, links.