On Tue, 29 Nov 2005, Mark Fredrickson wrote: > Here's a general question about CSS that I've been able to quite figure > out. If one has a DIV that will only appear once per page, which should > one use: a class or an id?
An oldie, but a goodie (beware obsolete code): http://www.hotwired.com/webmonkey/templates/print_template.htmlt?meta=/webmonkey/98/05/index3a_meta.html Is a reflection on how one might decide to choose which attribute to assign. > Classes are obviously useful at applying to multiple elements, or > applying multiple classes to one element. What advantages have that > classes do not? Specificity comes to mind, but the CSS rules regarding > this are hazy in my mind and I do not know if ids provide more > specificity than classes. ID's are in fact more specific than classes; the spec discusses a scheme involving a combination of logarithmic and arithmetic weighting. If you are nearly or entirely certain that you will only need to use a given component of a selector within a given page, then there's no reason why you shouldn't put it in an id context. Also, id is easier to work with when scripting, as a rule. With id's you merely need to check for the existence of an id in one line; with classnames you need to walk through all or part of the document tree, checking each node as you go along. -- Ben Henick "In the long run, men hit only what they aim Sitebuilder At-Large at. Therefore, though they should fail http://www.henick.net/ immediately, they had better aim high." [EMAIL PROTECTED] -- Henry David Thoreau ______________________________________________________________________ css-discuss [EMAIL PROTECTED] http://www.css-discuss.org/mailman/listinfo/css-d List wiki/FAQ -- http://css-discuss.incutio.com/ Supported by evolt.org -- http://www.evolt.org/help_support_evolt/
