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HTML How to Make a Website Responsive Web Design and Testing Build a Three Column Layout

John Silverstein
John Silverstein
6,290 Points
Posted by John Silverstein
John Silverstein
6,290 Points

I thought u cant give an html element more than one id, and u need to use classes for that.

If its possible to give the same type of html element more then one id, then why use classes at all?

Jason Anello
Jason Anello
Courses Plus Student 94,610 Points

Did you see an example of an element getting more than 1 id?

2 Answers

Samuel Ferree
Samuel Ferree
31,722 Points
Samuel Ferree
Samuel Ferree
31,722 Points

You can have multiple ID's that refer to the same HTML element (Although this is considered bad practice, and "Code Smell")

But you can't have a single ID that refers to multiple HTML Elements. this is the main use for classes.

<div class="round">
  This div will have the styles applied from .round
</div>
<div class="round">
  This div will also have those styles applied
</div>
Samuel Ferree
Samuel Ferree
31,722 Points
Samuel Ferree
Samuel Ferree
31,722 Points

To clarify, an XHTML element can have multiple ids, e.g.

<p id="foo" xml:id="bar">

Again, this is bad practice, and "Code Smell"

Kevin Korte
Kevin Korte
28,149 Points
Kevin Korte
Kevin Korte
28,149 Points

You are correct, you should only have one id per element. ID's and classes also have different css specificity, which is why it's so common to find classes as the main selector for css styles, as they have 1 point, vs an id that carries 10 points - the goal is to always keep css specificity as low as possible.