How to differentiate from the server side, between the first request of the browser (HTML file) and the following (images, CSS, scripts...)?

I'm programming a website with SEO friendly links, ie, put the page title or other descriptive text in the link, separated by slashes. For example: h*tp://www.domain.com/section/page-开发者_如何转开发title-bla-bla-bla/.

I redirect the request to the main script with mod_rewrite, but links in script, img and link tags are not resolved correctly. For example: assuming you are visiting the above link, the tag request the file at the URL h*tp://www.domain.com/section/page-title-bla-bla-bla/js/file.js, but the file is actually http://www.domain.com/js/file.js

I do not want to use a variable or constant in all HTML file URLs.

I'm trying to redirect client requests to a directory or to another of the server. It is possible to distinguish the first request for a page, which comes after? It is possible to do with mod_rewrite for Apache, or PHP?

I hope I explained well:)

Thanks in advance.

Using rewrite rules to fix the problem of relative paths is unwise and has numberous downsides.

Firstly, it makes things more difficult to maintain because there are hundreds of different links in your system.

Secondly and more seriously, you destroy cacheability. A resource requested from here:

http://www.domain.com/section/page-title-bla-bla-bla/js/file.js    

will be regarded as a different resource from

http://www.domain.com/section/some-other-page-title/js/file.js

and loaded two times, causing the number of requests to grow dozenfold.

What to do?

Fix the root cause of the problem instead: Use absolute paths

<script src="/js/file.js">

or a constant, or if all else fails the <base> tag.

This is an issue of resolving relative URIs. Judging by your description, it seems that you reference the other resources using relative URI paths: In /section/page-title-bla-bla-bla a URI reference like js/file.js or ./js/file.js would be resolved to /section/page-title-bla-bla-bla/js/file.js.

To always reference /js/file.js independet from the actual base URI path, use the absolute path /js/file.js. Another solution would be to set the base URI explicitly to / using the BASE element (but note that this will affect all relative URIs).