usage of class n id

[nidhi]

can anyone tell me when to use class and when to use id?is id also used to apply our style? class can b used any no. oftimes that i knw, n i think id can used once. what other differencesare there bw class n id?

[Jack McKalling]

That is correct one difference between those. IDs are not allowed (at least not in Xhtml strict) to be more than once. Classes do.Second, in your stylesheet, classes begin with a dot: .And IDs with a hash: #Like this:

p.common { ... }p#myfooter { ... }

So you'd use classes when you have commmonly used elements, or different elements, that you want to have the same style. Or IDs, when there is only one of them (but then you may still choose for a class). Next, IDs may come in handy when an element already has a class, but still needs more difference from the other elements with the same class. Like in this:

p.common { ... }p.common#first { ... }

Edited May 17, 2006 by Dan The Prof