What are the front-end pseudo-class selectors?
Front-end pseudo-class selectors include:hover, :active, :focus, :first-child, :last-child, :nth-child(), :nth-of-type() and :not( )wait. Detailed introduction: 1. The :hover pseudo-class selector is used to apply styles when the mouse is hovering over an element. It is often used to create interactive effects, such as changing its color or background when the mouse is hovering over a link; 2. :active pseudo-class Class selectors are used to apply styles when an element is activated, etc.
The operating system for this tutorial: Windows 10 system, DELL G3 computer.
Front-end pseudo-class selectors are a very important part of CSS. They allow us to select and apply styles based on the state or position of elements. In this article, we will introduce some common front-end pseudo-class selectors.
1. :hover pseudo-class selector
:hover pseudo-class selector is used to apply styles when the mouse is hovering over the element. It is often used to create interactive effects, such as changing the color or background of a link when the mouse is hovered over it.
Example:
a:hover { color: blue; }
2. :active pseudo-class selector
:active pseudo-class selector is used to apply styles when the element is activated. It is often used for click effects on buttons or links, such as changing the color or background of a button when the user clicks it.
Example:
button:active { background-color: yellow; }
3. :focus pseudo-class selector
:focus pseudo-class selector is used to apply styles when the element gets focus. It is often used on form elements, such as changing the border color or background of an input box when the user clicks on it.
Example:
input:focus { border-color: red; }
4. :first-child pseudo-class selector
:first-child pseudo-class selector is used to select the first child element of the parent element. It is often used to apply a special style to the first element in a list.
Example:
ul li:first-child { font-weight: bold; }
5. :last-child pseudo-class selector
:last-child pseudo-class selector is used to select the last child element of the parent element. It is often used to apply a special style to the last element in a list.
Example:
ul li:last-child { color: red; }
6. :nth-child() pseudo-class selector
:nth-child() pseudo-class selector is used to select the parent element child element at a specific position. It can accept a parameter that specifies the position of the child element to be selected.
Example:
ul li:nth-child(odd) { background-color: lightgray; }
7. :nth-of-type() pseudo-class selector
:nth-of-type() pseudo-class selector is used to select the parent A specific type of child element of an element. It can accept a parameter that specifies the position of the child element to be selected.
Example:
ul li:nth-of-type(2n) { color: blue; }
8. :not() pseudo-class selector
:not() pseudo-class selector is used to select elements that do not meet the specified conditions. It can accept a parameter that specifies the elements to exclude.
Example:
input:not([type="text"]) { display: none; }
These are common pseudo-class selectors on the front end, they can help us select and apply styles based on the state or position of elements. By flexibly using these pseudo-class selectors, we can add more interactive effects and personalized styles to web pages.
The above is the detailed content of What are the front-end pseudo-class selectors?. For more information, please follow other related articles on the PHP Chinese website!

HTML and React can be seamlessly integrated through JSX to build an efficient user interface. 1) Embed HTML elements using JSX, 2) Optimize rendering performance using virtual DOM, 3) Manage and render HTML structures through componentization. This integration method is not only intuitive, but also improves application performance.

React efficiently renders data through state and props, and handles user events through the synthesis event system. 1) Use useState to manage state, such as the counter example. 2) Event processing is implemented by adding functions in JSX, such as button clicks. 3) The key attribute is required to render the list, such as the TodoList component. 4) For form processing, useState and e.preventDefault(), such as Form components.

React interacts with the server through HTTP requests to obtain, send, update and delete data. 1) User operation triggers events, 2) Initiate HTTP requests, 3) Process server responses, 4) Update component status and re-render.

React is a JavaScript library for building user interfaces that improves efficiency through component development and virtual DOM. 1. Components and JSX: Use JSX syntax to define components to enhance code intuitiveness and quality. 2. Virtual DOM and Rendering: Optimize rendering performance through virtual DOM and diff algorithms. 3. State management and Hooks: Hooks such as useState and useEffect simplify state management and side effects handling. 4. Example of usage: From basic forms to advanced global state management, use the ContextAPI. 5. Common errors and debugging: Avoid improper state management and component update problems, and use ReactDevTools to debug. 6. Performance optimization and optimality

Reactisafrontendlibrary,focusedonbuildinguserinterfaces.ItmanagesUIstateandupdatesefficientlyusingavirtualDOM,andinteractswithbackendservicesviaAPIsfordatahandling,butdoesnotprocessorstoredataitself.

React can be embedded in HTML to enhance or completely rewrite traditional HTML pages. 1) The basic steps to using React include adding a root div in HTML and rendering the React component via ReactDOM.render(). 2) More advanced applications include using useState to manage state and implement complex UI interactions such as counters and to-do lists. 3) Optimization and best practices include code segmentation, lazy loading and using React.memo and useMemo to improve performance. Through these methods, developers can leverage the power of React to build dynamic and responsive user interfaces.

React is a JavaScript library for building modern front-end applications. 1. It uses componentized and virtual DOM to optimize performance. 2. Components use JSX to define, state and attributes to manage data. 3. Hooks simplify life cycle management. 4. Use ContextAPI to manage global status. 5. Common errors require debugging status updates and life cycles. 6. Optimization techniques include Memoization, code splitting and virtual scrolling.

React's future will focus on the ultimate in component development, performance optimization and deep integration with other technology stacks. 1) React will further simplify the creation and management of components and promote the ultimate in component development. 2) Performance optimization will become the focus, especially in large applications. 3) React will be deeply integrated with technologies such as GraphQL and TypeScript to improve the development experience.


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

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft

SecLists
SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

Notepad++7.3.1
Easy-to-use and free code editor

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.