HTML - How can I check if a file (.js or .css) was loaded or picked up from the cache?

Question

First, I needed a way to force browser always load .css and .js files. I solved it by putting a sufix in the files:

Before:

Answer 1

It is browser responsibility area to load resources from server or take it from cache. From client code you cannot determine the source that was actually used (if you don't load resources dynamically using ajax). Only you can is look at the Network tab in Developer Tools (or Firebug).