The class attribute assigns one or more classnames to the <li> tag.
Classnames are defined in a stylesheet or in a local <style> element.
Classes, i.e. classnames, are used to style elements.
A class attribute styling 3 <li> elements.
<style>
.job-title { color:teal; padding:3px 0; margin:5px 0; font-style:italic; }
</style>
<ol>
<li class="job-title ">Designers</li>
<li class="job-title ">Developers</li>
<li class="job-title ">Managers</li>
</ol>
Classes (i.e. classnames) are used for styling the li element.
Multiple classnames are separated by a space.
JavaScript uses classes to access elements by classname.
Tip: class is a global attribute that can be applied to any HTML element.
<li class="classnames">
| Value | Description |
|---|---|
| classnames | One or more space-separated class names. |
A class attribute styling <li> elements.
Clicking the button toggles a classname that changes the background color for all items.
<style>
.job-title { color:teal; padding:3px 0; margin:5px 0; font-style:italic; }
.moccasin { background-color:moccasin; }
</style>
<ol>
<li class="job-title ">Designers</li>
<li class="job-title ">Developers</li>
<li class="job-title ">Managers</li>
</ol>
<br />
<button onclick="toggle();">Toggle class</button>
<script>
let toggle = () => {
let elements = document.getElementsByClassName("job-title");
[].forEach.call(elements, element => element.classList.toggle("moccasin"));
}
</script>
Two CSS classes are defined in the <style> element.
Clicking the button retrieves all the <li> elements using the classname.
Javascript then iterates over the elements and toggle another classname changing the list item background color.
Here is when class support started for each browser:
 Chrome
|
1.0 | Sep 2008 |
 Firefox
|
1.0 | Sep 2002 |
 IE/Edge
|
1.0 | Aug 1995 |
 Opera
|
1.0 | Jan 2006 |
 Safari
|
1.0 | Jan 2003 |
