Which combing css technique?
- by DotnetShadow
Hi there,
Which of the following would you say is the best way to go when combining files for CSS:
Say I have a master.css file that is used across all pages on my website (page1.aspx, page2.aspx)
Page1.aspx - A specific page that has some unique css that is only ever used on that page, so I create a page1.css and it also uses another css grids.css
Page2.aspx - Another specific page that is different from all other pages on the site and is different to page1.aspx, I'll name this page2.aspx and make a page2.css this doesn't use grids.css
So would you combine the scripts as:
Option1:
Combine scripts
csshandler.axd?d=master.css,page1.css,grids.css
when visiting page1
Combine
scripts
csshandler.axd?d=master.css,page2.css
when visiting page2
Benefits: Page specific, rendering quicker since only selectors for that page need to be matched up no unused selectors
Drawback: Multiple combinations of master.css + page specific hence master.css has to be downloaded for each page
Option2:
Combine all scripts whether a page needs them or not
csshandler.axd?d=master.css,page1.css,page2.css,grids.css
(master, page1 and page2)
that way it gets cached as one. The problem is that rendering maybe slower since it will have to try and match EVERY selector in the css with selectors on the page even the missing ones, so in the case of page2.aspx that doesn't use grids.css the selectors in grids.css will need to be parsed to see if they are in page2 which means rendering will be slow
Benefits: One file will ever be downloaded and cached doesn't matter what page you visit
Drawback: Unused selectors will need to be parsed by the browser slower rendering
Option3:
Leave the master file on it's own and only combine other scripts (the benefit of this is because master is used across all pages there is a chance that this is cached so doesn't need to keep on downloading
csshandler.axd?d=Master.css
csshandler.axd?d=page1.css,grids.css
Benefits: master.css file can be cached doesn't matter what page you visit. Not many unused selectors as page spefic is applied
Drawback: Initially minimum of 2 HTTP request will have to be made
What do you guys think?
Cheers
DotnetShadow