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HTML

Posted by David Schriever
David Schriever
1,777 Points

why use id's?

Hello! I have a question. Why would I use ID's in html? why not just use class for all? Seems the only difference is that IDs can only be used once, so why woulds i add this restriction on myself?

4 Answers

Matt Milburn
Matt Milburn
20,787 Points

Hi David,

You are correct, sir.

  1. Use classes for styling. Do not apply styles to IDs unless you want to be married to your solutions.
  2. Use IDs for things like javascript, linking form labels to their inputs, etc.
  3. Don't let anyone tell you otherwise. It should not be optional.
David Schriever
David Schriever
1,777 Points

Thanks Matt, good to be right. :D

Emeka Okoye
Emeka Okoye
2,489 Points
Emeka Okoye
Emeka Okoye
2,489 Points

It's always best to use classes to adher to DRY (Don't Repeat Yourself) programming. However, there are times using IDs are useful.

E.g when working with JavaScript or JQuery and you need to get an element by ID.

It's also useful when running content experiments in Google Analytics but you can also use classes for that.

Lastly, certain elements rely on IDs e.g anchor scrolling and working with accordions in twitter bootstrap.

These are all examples but generally when I code a webpage, I only use classes and then I add IDs as and when I need them.

Kallil Belmonte
Kallil Belmonte
35,561 Points
Kallil Belmonte
Kallil Belmonte
35,561 Points

Hi David, take a look at this article (it explains better than me):

https://css-tricks.com/the-difference-between-id-and-class/

Dom Farnham
Dom Farnham
19,421 Points
Dom Farnham
Dom Farnham
19,421 Points

Hello David,

There are some situations where you wish to identify and manipulate a paticular element, as opposed to all elements of the same type. For example, you may wish to use JavaScript to add an event handler, like onclick, to a certain button element. Or, you may wish to use CSS to style the button differently to other buttons.

Dom