This is not a "coding question", but more something like "how does it work?".
Let's consider I want to show an heavy pic on page 2. If I'm preloading this pic on a page 1 (no display) and click on the page-2-link before it's fully loaded... What happens?
=> The page 2 loads and the end of heavy pic is also loaded, or cache doesn't work for partially loaded files?
Thanks for your explanations,
CH
In theory its very possible that part of the response gets cached, either by the web browser or by a proxy server between the end user and the web server. http supports range requests, where the client can ask for a specific slice of the total resource(like an image). All the big name web servers support range requests.
I really don't know off hand if any web browsers cache a partially downloaded resource, although it would be a simple test - clear the web browsers cache, hit a web page that loads a large external object, stop loading midway through. Make sure the webserver sends the following headers along with the response.
cache-control: max-age=10000
accept-ranges: bytes
Now make the request again but look at the http headers of the request to look for the browser asking for partial contents like Range: bytes=100000-90000000. It would obviously only ask for partial content if it had partially cached the file.
The max-age header tells the browser the file is cachable for a while, and the accept-ranges headers tells the browser the web server is capable of servicing partial content requests.
