What is the difference between class and id
What is the difference between
id and class? What does ID mean? What does class mean? Today we will introduce to you these two easily confused concepts
You can see the use of id and class in div, span, p tags, h1, h2 and other tags. id and class are very commonly used tagsAttributes.
<div id="header"></div> <div class="menu"></div>
The above is what we often see id and class existing in div tags. "Header" and "menu" are custom CSS names. (Pay attention to the case of CSS naming, and do not name css starting with a number)
Explanation on the usage of id and class
1. Differences in usage
id is unique, in a web page The same name can only be used once; a class named
class can be used countless times in a web page.
2. Difference in css
id in css code is a class named starting with "#" pound sign
class is named in css code starting with "." Class names starting with a lowercase period symbol
What do id and class mean?
Both id and class can be used in any tag on the web page. Generally, IDs are used for more important parts and special boxes, while classes are used for small parts that are not important or small structures. id calls the style selector named with the "#" pound sign in CSS, and class calls the style selector named with "." English half-width lowercase period in CSS.
I believe that through this article everyone should have a deep impression of their differences. For more exciting content, please pay attention to php Chinese website Other related articles!
Related reading:
The above is the detailed content of What is the difference between class and id. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
How to set password protection for export PDF on PS
Apr 06, 2025 pm 04:45 PM
Export password-protected PDF in Photoshop: Open the image file. Click "File"> "Export"> "Export as PDF". Set the "Security" option and enter the same password twice. Click "Export" to generate a PDF file.
The difference between H5 and mini-programs and APPs
Apr 06, 2025 am 10:42 AM
H5. The main difference between mini programs and APP is: technical architecture: H5 is based on web technology, and mini programs and APP are independent applications. Experience and functions: H5 is light and easy to use, with limited functions; mini programs are lightweight and have good interactiveness; APPs are powerful and have smooth experience. Compatibility: H5 is cross-platform compatible, applets and APPs are restricted by the platform. Development cost: H5 has low development cost, medium mini programs, and highest APP. Applicable scenarios: H5 is suitable for information display, applets are suitable for lightweight applications, and APPs are suitable for complex functions.
Why do you need to call Vue.use(VueRouter) in the index.js file under the router folder?
Apr 05, 2025 pm 01:03 PM
The necessity of registering VueRouter in the index.js file under the router folder When developing Vue applications, you often encounter problems with routing configuration. Special...
How to use XPath to search from a specified DOM node in JavaScript?
Apr 04, 2025 pm 11:15 PM
Detailed explanation of XPath search method under DOM nodes In JavaScript, we often need to find specific nodes from the DOM tree based on XPath expressions. If you need to...
Difference between centos and ubuntu
Apr 14, 2025 pm 09:09 PM
The key differences between CentOS and Ubuntu are: origin (CentOS originates from Red Hat, for enterprises; Ubuntu originates from Debian, for individuals), package management (CentOS uses yum, focusing on stability; Ubuntu uses apt, for high update frequency), support cycle (CentOS provides 10 years of support, Ubuntu provides 5 years of LTS support), community support (CentOS focuses on stability, Ubuntu provides a wide range of tutorials and documents), uses (CentOS is biased towards servers, Ubuntu is suitable for servers and desktops), other differences include installation simplicity (CentOS is thin)
What are the different ways of promoting H5 and mini programs?
Apr 06, 2025 am 11:03 AM
There are differences in the promotion methods of H5 and mini programs: platform dependence: H5 depends on the browser, and mini programs rely on specific platforms (such as WeChat). User experience: The H5 experience is poor, and the mini program provides a smooth experience similar to native applications. Communication method: H5 is spread through links, and mini programs are shared or searched through the platform. H5 promotion methods: social sharing, email marketing, QR code, SEO, paid advertising. Mini program promotion methods: platform promotion, social sharing, offline promotion, ASO, cooperation with other platforms.
What is the difference between syntax for adding columns in different database systems
Apr 09, 2025 pm 02:15 PM
不同数据库系统添加列的语法为：MySQL：ALTER TABLE table_name ADD column_name data_type;PostgreSQL：ALTER TABLE table_name ADD COLUMN column_name data_type;Oracle：ALTER TABLE table_name ADD (column_name data_type);SQL Server：ALTER TABLE table_name ADD column_name data_
The difference in output results of console.log: Why do the same variables have different printing methods but different results?
Apr 04, 2025 am 11:48 AM
In-depth discussion of the differences in console.log output in this article will analyze the reasons why the output results of console.log function in a piece of code are different. Code snippets involve URL parameter resolution...
