HTML Classes
The HTML `class` attribute is
The HTML class attribute is
used to specify a class for an HTML element.
Multiple HTML elements can share the same class.
The class Attribute
The class attribute is often used to point
to a class name in a style sheet. It can also be used by JavaScript to access and
manipulate elements with the specific class name.
In the following example we have three <div> elements
with a class attribute with the value of
"city". All of the three <div>
elements will be styled equally according to the .city
style definition in the head section:
Example
Example Code
htmlIn the following example we have two <span> elements
with a class attribute with the value of
"note". Both <span>
elements will be styled equally according to the .note
style definition in the head section:
Example
Example Code
htmlTip: The class attribute can be used on any HTML element.
Note: The class name is case sensitive!
Tip: You can learn much more about CSS in our CSS Tutorial.
The Syntax For Class
To create a class; write a period (.) character, followed by a class name. Then, define the CSS properties within curly braces {}:
Example
Example Code
htmlMultiple Classes
HTML elements can belong to more than one class.
To define multiple classes, separate the class names with a space, e.g. <div
class="city main">. The element will be styled according to all the
classes specified.
In the following example, the first <h2> element belongs to both the city class and also to the main class,
and will get the CSS styles from both of the classes:
Example
Example Code
htmlDifferent Elements Can Share Same Class
Different HTML elements can point to the same class name.
In the following example, both <h2> and <p>
point to the "city" class
and will share the same style:
Example
Example Code
htmlUse of the class Attribute in JavaScript
The class name can also be used by JavaScript to perform certain tasks for specific elements.
JavaScript can access elements with a specific class name with the getElementsByClassName() method:
Example
Example Code
html<script>
function myFunction() {
var x = document.getElementsByClassName("city");
for (var i = 0; i < x.length;
i++) {
x[i].style.display = "none";
}
}
</script>Don't worry if you don't understand the code in the example above.
You will learn more about JavaScript in our HTML JavaScript chapter, or you can study our JavaScript Tutorial.
Chapter Summary
- The HTML
classattribute specifies one or more class names for an element
- Classes are used by CSS and JavaScript to select and access specific elements
- The
classattribute can be used on any HTML element
- The class name is case sensitive
- Different HTML elements can point to the same class name
- JavaScript can access elements with a specific class name with the
getElementsByClassName()method
Video: HTML Class
Interactive Code Examples
HTML Example 1
htmlHTML Example 2
htmlHTML Example 3
htmlHTML Example 4
htmlHTML Example 5
htmlHTML Example 6
html<script>
function myFunction() {
var x = document.getElementsByClassName("city");
for (var i = 0; i < x.length;
i++) {
x[i].style.display = "none";
}
}
</script>