In HTML5, the class attribute can define the class name of the element. It is often used to point to the class of the style sheet (class selector). It can also be used in JavaScript to modify the class name of the HTML element and modify the style; syntax Format "<element class="classname">". <element class="classname">
The operating environment of this tutorial: Windows 7 system, HTML5 version, Dell G3 computer.
HTML5 class attribute
The class attribute defines the class name of the element. The
class attribute is typically used to point to the class of a style sheet (i.e. the CSS .class selector). However, it can also be used in JavaScript (via the HTML DOM) to modify the class name of an HTML element.
Syntax
<element class="classname">
classname: Specifies the name of the class of the element. To specify multiple classes for an element, separate the class names with spaces. . Multiple classes are allowed for HTML elements.
Name rules:
must start with the letters A-Z or a-z
can be the following characters: (A-Za- z), numbers (0-9), bars ("-"), and underscores ("_")
In HTML, class names are case-sensitive
Example:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <style> .center { text-align:center; } </style> </head> <body> <h1 id="标题居中">标题居中</h1> <p class="center">段落居中。</p> </body> </html>
Rendering:
html video tutorial》】
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