What is the most difficult technical problem you have encountered? How did you solve it?

What are the commonly used libraries? Commonly used front-end development tools? What applications or components have you developed?

How to reconstruct the page?

List the features that make IE different from other browsers?

Which book says that 99% of websites need to be refactored?

What are graceful degradation and progressive enhancement?

What are the ways for WEB applications to actively push data from the server to the client?

Have your own opinions on the advantages and disadvantages of Node?

*(Advantages) Because Node is event-driven and non-blocking, it is very suitable for handling concurrent requests.
Therefore, the proxy server built on Node is better than servers implemented by other technologies (such as Ruby) Performance is much better.
In addition, the client code that interacts with the Node proxy server is written in the javascript language,
Therefore, both the client and the server are written in the same language, which is a very beautiful thing.

* (Disadvantages) Node is a relatively new open source project, so it is not stable. It is always changing,
and lacks enough third-party library support. It looks like what Ruby/Rails looked like back then.

What performance optimization methods do you have?

(See Yahoo’s 14 performance optimization principles).

(1) Reduce the number of http requests: CSS Sprites, JS, CSS source code compression, appropriate image size control; web page Gzip, CDN hosting, data cache, image server.

(2) Front-end template JS data reduces bandwidth waste caused by HTML tags. The front-end uses variables to save AJAX request results. Each time it operates local variables, there is no need to request, reducing the number of requests

( 3) Use innerHTML instead of DOM operations to reduce the number of DOM operations and optimize javascript performance.

(4) When there are many styles to be set, set className instead of directly operating style.

(5) Use less global variables and cache the results of DOM node search. Reduce IO read operations.

(6) Avoid using CSS Expression (css expression), also known as Dynamic properties (dynamic properties).

(7) Image preloading, put the style sheet at the top, put the script at the bottom and add a timestamp.

(8) Avoid using table in the main layout of the page. The table will not be displayed until the content is completely downloaded. The display is slower than the div css layout.

What are the http status codes? What do they mean?

100-199 is used to specify certain actions that the client should take accordingly.
200-299 is used to indicate that the request was successful.
300-399 is used for files that have been moved and is often included in the location header information to specify the new address information.
400-499 is used to indicate client errors. 400 1. The semantics are incorrect and the current request cannot be understood by the server. 401 The current request requires user authentication. 403 The server has understood the request but refused to execute it.
500-599 is used to support server errors. 503 – Service Unavailable

What happens in the process from entering the URL to the completion of page loading and display of a page? (The more detailed the process, the better)

Find the browser cache
DNS resolution, find the IP address corresponding to the domain name, redirect (301), issue a second GET request
Perform HTTP Protocol session
The client sends a header (request header)
The server returns a header (response header)
The html document starts downloading
The document tree is established, and the file with the MIME type specified according to the mark request
File display
[
The work done by the browser is roughly divided into the following steps:

Loading: Perform domain name resolution according to the requested URL, initiate a request to the server, and receive files (HTML, JS , CSS, images, etc.).

Parsing: Perform syntax analysis on loaded resources (HTML, JS, CSS, etc.), and recommend corresponding internal data structures (such as HTML DOM tree, JS (object) attribute table, CSS style rules Wait)
}

In addition to front-end, do you know any other technologies? What is your greatest skill?

What are your commonly used development tools and why?

How do you understand the position of front-end interface engineer? What are its prospects?

The front-end is the programmer who is closest to the user, closer than the back-end, database, product manager, operation, and security.
1. Realize interface interaction
2. Improve user experience
3. With Node.js, the front-end can realize some things on the server side

The front-end is the programmer closest to the user, the front-end The ability is to make the product evolve from 90 points to 100 points, or even better,

Participate in the project, quickly complete the renderings with high quality, accurate to 1px;

Work with team members, UI Design, communication with product managers;

Good page structure, page reconstruction and user experience;

Dealing with hacks, compatibility, and writing beautiful code formats;

Optimize the server and embrace the latest front-end technology.

What do you think about working overtime?

Working overtime is like borrowing money. The principle should be------to help the urgent, not to save the poor.

How do you usually manage your projects?

The early team must determine the global style (globe.css), encoding mode (utf-8), etc.

The writing habits must be consistent (for example, they all use inheritance writing, and single styles are written in one line) ;

Mark the style writer, and mark each module in time (mark the place where the key style is called);

Mark the page (such as the beginning and end of the page module);

CSS and HTML sub -folder are stored in parallel, and the naming must be uniform (for example Style.css)

# JS sub -folder to save the people with the JS function as the English translation; Images.png png8 format files should be integrated as much as possible to facilitate future management


How to design a sudden large-scale concurrency architecture?

Let’s talk about some of the most popular things recently? What websites do you often visit?

Node.js, Mongodb, npm, MVVM, MEAN, three.js

How to improve the user experience on the mobile terminal (Android IOS)?

Clear Visual vertical lines, grouping of information, ultimate subtraction,

Relying on plain text to confirm passwords, reasonable keyboard usage,


What is your role in the current team and what significant role do you play?

What do you think is a Full Stack developer?

Introduce one of your most proud works?

What are your strengths? What are the disadvantages?

How to manage a front-end team?

What are you learning recently? Can you talk about your plans for yourself in the next 3 or 5 years?

Want to ask a question about the company?

Ask the company a question:

How does the front-end team work (the process of implementing a product)?
What is the company’s salary structure like?