css sprite is a way to handle background images on web pages. It actually includes all the scattered pictures involved in a page into one big picture, and then applies the big picture to the web page; in this way, when the user visits the page, he only needs to send a request to the service, and the The background image can be fully displayed.
The operating environment of this tutorial: Windows 7 system, CSS3&&HTML5 version, Dell G3 computer.
What is a css sprite?
"CSS sprite", also known as usually interpreted as "CSS image stitching", "CSS map positioning" or "CSS image sprite", "CSS sprite", is A web image application processing method. In fact, it is to include all the scattered pictures involved in a page into one large picture. In this way, when the page is accessed, the loaded pictures will not be displayed slowly one by one as before. .
When the user visits the page, he only needs to send a request to the service, and all the background images in the web page can be displayed.
For example:
Advantages
Using CSS Sprites can effectively reduce the http requests of web pages, thus Greatly improve the performance of the page, which is also the biggest advantage of CSS Sprites and the main reason why it is widely spread and applied;
CSS Sprites can reduce the bytes of images. I have compared The bytes of merging three pictures into one picture many times are always smaller than the sum of bytes of these three pictures.
Solve the problem of web designers in naming pictures. They only need to name a collection of pictures. There is no need to name each small element, thereby improving Improve the efficiency of web page production.
It is easy to change the style. You only need to modify the color or style of one or a few pictures, and the style of the entire web page can be changed. Maintenance is more convenient.
Use of sprite technology
css sprite (sprite) is actually to merge multiple images into one Inside the picture, the background of the web page is laid out through CSS background positioning technology. When images need to be used, the current stage is to use the CSS attribute background-image combined with background-repeat, background-position, etc. to display the image.
Example:
Sprite analysis:
<!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <title></title> <meta name="viewport" content="width=device-width, initial-scale=1"> <style> *{ margin: 0; padding: 0; } .sprites{ width: 200px; margin: 50px auto; } .sprites div{ margin: 5px; } .sprites span{ float: left; width: 20px; height:20px; background: url('./images/icon.png');/* 引用精灵图 */ background-size: 60px 40px; } .sprites1{ background-position: 0 0; } .sprites2{ background-position: -20px 0 !important; } .sprites3{ background-position: 0 -20px !important; } .sprites4{ background-position: -20px -20px !important; } .sprites5{ background-position: -40px 0 !important; } </style> </head> <body> <div class="sprites"> <div><span class="sprites1"></span>付款图标</div> <div><span class="sprites2"></span>存款图标</div> <div><span class="sprites3"></span>删除图标</div> <div><span class="sprites4"></span>粘贴图标</div> <div><span class="sprites5"></span>笑脸图标</div> </div> </body> </html>
The above is the detailed content of what is css sprite. For more information, please follow other related articles on the PHP Chinese website!

React is a front-end framework for building user interfaces; a back-end framework is used to build server-side applications. React provides componentized and efficient UI updates, and the backend framework provides a complete backend service solution. When choosing a technology stack, project requirements, team skills, and scalability should be considered.

The relationship between HTML and React is the core of front-end development, and they jointly build the user interface of modern web applications. 1) HTML defines the content structure and semantics, and React builds a dynamic interface through componentization. 2) React components use JSX syntax to embed HTML to achieve intelligent rendering. 3) Component life cycle manages HTML rendering and updates dynamically according to state and attributes. 4) Use components to optimize HTML structure and improve maintainability. 5) Performance optimization includes avoiding unnecessary rendering, using key attributes, and keeping the component single responsibility.

React is the preferred tool for building interactive front-end experiences. 1) React simplifies UI development through componentization and virtual DOM. 2) Components are divided into function components and class components. Function components are simpler and class components provide more life cycle methods. 3) The working principle of React relies on virtual DOM and reconciliation algorithm to improve performance. 4) State management uses useState or this.state, and life cycle methods such as componentDidMount are used for specific logic. 5) Basic usage includes creating components and managing state, and advanced usage involves custom hooks and performance optimization. 6) Common errors include improper status updates and performance issues, debugging skills include using ReactDevTools and Excellent

React is a JavaScript library for building user interfaces, with its core components and state management. 1) Simplify UI development through componentization and state management. 2) The working principle includes reconciliation and rendering, and optimization can be implemented through React.memo and useMemo. 3) The basic usage is to create and render components, and the advanced usage includes using Hooks and ContextAPI. 4) Common errors such as improper status update, you can use ReactDevTools to debug. 5) Performance optimization includes using React.memo, virtualization lists and CodeSplitting, and keeping code readable and maintainable is best practice.

React combines JSX and HTML to improve user experience. 1) JSX embeds HTML to make development more intuitive. 2) The virtual DOM mechanism optimizes performance and reduces DOM operations. 3) Component-based management UI to improve maintainability. 4) State management and event processing enhance interactivity.

React components can be defined by functions or classes, encapsulating UI logic and accepting input data through props. 1) Define components: Use functions or classes to return React elements. 2) Rendering component: React calls render method or executes function component. 3) Multiplexing components: pass data through props to build a complex UI. The lifecycle approach of components allows logic to be executed at different stages, improving development efficiency and code maintainability.

React Strict Mode is a development tool that highlights potential issues in React applications by activating additional checks and warnings. It helps identify legacy code, unsafe lifecycles, and side effects, encouraging modern React practices.

React Fragments allow grouping children without extra DOM nodes, enhancing structure, performance, and accessibility. They support keys for efficient list rendering.


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

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

SublimeText3 Linux new version
SublimeText3 Linux latest version

SublimeText3 Chinese version
Chinese version, very easy to use