The class attribute assigns one or more classnames to the <pre> 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 a <pre> element.
SELECT FirstName, LastName FROM Customer ORDER BY LastName
<style>
.pre {background: whitesmoke; width: 350px;padding: 20px 5px;}
</style>
<pre class="pre">
SELECT FirstName, LastName
FROM Customer ORDER BY LastName
</pre>
Classes (i.e. classnames) are used for styling the pre 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.
<pre class="classnames">
| Value | Description |
|---|---|
| classnames | One or more space-separated class names. |
A class attribute styling a <pre> element.
Clicking the button toggles a classname that changes the background and text colors.
SELECT FirstName, LastName FROM Customer ORDER BY LastName
<style>
.pre {background: whitesmoke; width: 350px;padding: 20px 5px;}
.pre-dark {background: #222;color: white;}
</style>
<pre id="mypre" class="pre">
SELECT FirstName, LastName
FROM Customer ORDER BY LastName
</pre>
<br />
<button onclick="toggle();">Toggle class</button>
<script>
let toggle = () => {
let element = document.getElementById("mypre");
element.classList.toggle("pre-dark");
}
</script>
Two CSS classes are defined in the <style> element.
The class attribute in <pre> assigns a single classname.
Repeatedly clicking the button toggles another class, changing the background and text color of the <pre> into dark mode.
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 |
Back to <pre>
