search
HomeWeb Front-endJS Tutorial2018 latest front-end interview questions four

This time we bring you the latest front-end interview questions in 2018. We know that before you enter a company, the interview stage is an essential part. This time, the common front-end interview questions are sorted and summarized to help you. Get over the hump of front-end interviews. Let’s take a look.

[Related recommendations: Front-end interview questions (2020)]

1. What is FOUC (flash without style content)? How do you avoid FOUC?

If you use the import method to import CSS, some pages will have some strange phenomena in Internet Explorer under Windows: the page content will flash without style for a moment. This phenomenon is called Flash of Unstyled Content, referred to as FOUC.

The reasons are roughly as follows:

1. Use the import method to import the style sheet.

          2. Place the style sheet at the bottom of the page

            3. There are several style sheets placed in different locations in the html structure.

In fact, the principle is very clear: when the style table is late than the structural HTML, when loading to this style table, the page will stop the previous rendering. After this style sheet is downloaded and parsed, the page will be re-rendered, resulting in a brief blurry screen phenomenon.

Solution:

Use the LINK tag to place the style sheet in the document HEAD.

2. Please explain what ARIA and screen readers are, and how to make the website accessible.

                                                                                              ARIA provide solutions for Web app to meet the different needs of users. Build a bridge between users and software.

The new HTML5 standard adds aria-* tag attributes, the full name is Accessible Rich Internet Application. Used in conjunction with the role tag attribute.

The role attribute indicates the actual role of a non-standard tag. For example, if you use a div as a button, then set the div's role="button", and the auxiliary tool can recognize that it is actually a button. The function of aria-* is to describe the specific information of this tag in the visual situation.

The simplest application is, for example,

           < div role=”checkbox” aria-checked=”checked”>

The auxiliary tool will know that this div is actually a checkbox role and is in the selected state.

3. Please explain the advantages and disadvantages of CSS animation and JavaScript animation.

1. CSS3 animation is only compatible with Ie10+, js animation is compatible with almost all browsers;

2. JS animation is more flexible, CSS3 animation is simpler

3. JS animation has high reusability

  4. In terms of time scale, CSS animation granularity is relatively coarse, and JS animation can be finer;

  5. Browser CSS animation with poor frame rate can be done To degrade gracefully, additional code needs to be written for js code

6. Under certain conditions, css animation performance is better than JS animation; (for browsers with webkit kernel, js performs expensive tasks without causing layout and In the case of repaint)

7.css3 has natural time support such as (animationENd and transitionEnd)

4. What is cross-domain resource sharing (CORS)? What problem is it used to solve?

When using ajax cross-domain request, the browser reports an error: Modification in this way would require too much engineering effort, so CORS, a relatively simple and efficient technology, is used. Compared with JOSP, CORS is more efficient. JSONP can only implement GET requests due to its principle, while CORS supports all types of HTTP requests. Using CORS, you can use ordinary ajax to achieve cross-domain

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the PHP Chinese website!

Related reading:

2018 latest front-end interview questions one

2018 latest front-end interview questions

2018 latest front-end interview questions three

The above is the detailed content of 2018 latest front-end interview questions four. For more information, please follow other related articles on the PHP Chinese website!

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Python vs. JavaScript: Choosing the Right Tool for the JobPython vs. JavaScript: Choosing the Right Tool for the JobMay 08, 2025 am 12:10 AM

Whether to choose Python or JavaScript depends on the project type: 1) Choose Python for data science and automation tasks; 2) Choose JavaScript for front-end and full-stack development. Python is favored for its powerful library in data processing and automation, while JavaScript is indispensable for its advantages in web interaction and full-stack development.

Python and JavaScript: Understanding the Strengths of EachPython and JavaScript: Understanding the Strengths of EachMay 06, 2025 am 12:15 AM

Python and JavaScript each have their own advantages, and the choice depends on project needs and personal preferences. 1. Python is easy to learn, with concise syntax, suitable for data science and back-end development, but has a slow execution speed. 2. JavaScript is everywhere in front-end development and has strong asynchronous programming capabilities. Node.js makes it suitable for full-stack development, but the syntax may be complex and error-prone.

JavaScript's Core: Is It Built on C or C  ?JavaScript's Core: Is It Built on C or C ?May 05, 2025 am 12:07 AM

JavaScriptisnotbuiltonCorC ;it'saninterpretedlanguagethatrunsonenginesoftenwritteninC .1)JavaScriptwasdesignedasalightweight,interpretedlanguageforwebbrowsers.2)EnginesevolvedfromsimpleinterpreterstoJITcompilers,typicallyinC ,improvingperformance.

JavaScript Applications: From Front-End to Back-EndJavaScript Applications: From Front-End to Back-EndMay 04, 2025 am 12:12 AM

JavaScript can be used for front-end and back-end development. The front-end enhances the user experience through DOM operations, and the back-end handles server tasks through Node.js. 1. Front-end example: Change the content of the web page text. 2. Backend example: Create a Node.js server.

Python vs. JavaScript: Which Language Should You Learn?Python vs. JavaScript: Which Language Should You Learn?May 03, 2025 am 12:10 AM

Choosing Python or JavaScript should be based on career development, learning curve and ecosystem: 1) Career development: Python is suitable for data science and back-end development, while JavaScript is suitable for front-end and full-stack development. 2) Learning curve: Python syntax is concise and suitable for beginners; JavaScript syntax is flexible. 3) Ecosystem: Python has rich scientific computing libraries, and JavaScript has a powerful front-end framework.

JavaScript Frameworks: Powering Modern Web DevelopmentJavaScript Frameworks: Powering Modern Web DevelopmentMay 02, 2025 am 12:04 AM

The power of the JavaScript framework lies in simplifying development, improving user experience and application performance. When choosing a framework, consider: 1. Project size and complexity, 2. Team experience, 3. Ecosystem and community support.

The Relationship Between JavaScript, C  , and BrowsersThe Relationship Between JavaScript, C , and BrowsersMay 01, 2025 am 12:06 AM

Introduction I know you may find it strange, what exactly does JavaScript, C and browser have to do? They seem to be unrelated, but in fact, they play a very important role in modern web development. Today we will discuss the close connection between these three. Through this article, you will learn how JavaScript runs in the browser, the role of C in the browser engine, and how they work together to drive rendering and interaction of web pages. We all know the relationship between JavaScript and browser. JavaScript is the core language of front-end development. It runs directly in the browser, making web pages vivid and interesting. Have you ever wondered why JavaScr

Node.js Streams with TypeScriptNode.js Streams with TypeScriptApr 30, 2025 am 08:22 AM

Node.js excels at efficient I/O, largely thanks to streams. Streams process data incrementally, avoiding memory overload—ideal for large files, network tasks, and real-time applications. Combining streams with TypeScript's type safety creates a powe

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

MinGW - Minimalist GNU for Windows

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.

MantisBT

MantisBT

Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

VSCode Windows 64-bit Download

VSCode Windows 64-bit Download

A free and powerful IDE editor launched by Microsoft

EditPlus Chinese cracked version

EditPlus Chinese cracked version

Small size, syntax highlighting, does not support code prompt function

WebStorm Mac version

WebStorm Mac version

Useful JavaScript development tools