Today, I will recommend a few recommended practices for writing JavaScript asynchronous code. Each scenario has a corresponding eslint rule, and you can choose to configure it. no-async-promise-executor Passing an async function to the constructor of new Promise is not recommended. // ❌ new Promise(async (resolve, reject) => {}); // ✅ new Promise((resolve, reject) => […]

Follow me on Twitter, I’d love to hear your suggestions for themes or improvements /Chris You may be completely new to JavaScript , or you may have only used it sporadically over the years. One thing is clear though – a lot has changed, and there are some features you should use. This post describes

CSS files are render-blocking resources : they must be loaded and processed before the browser can render the page. Web pages that contain unnecessarily large styles take longer to render. In this guide, you’ll learn how to lazy load non-critical CSS with the goal of optimizing the critical rendering path and improving First Contentful Paint

Star the front-end canteen and eat every meal! Because of the change in the recommendation mechanism of the official account, if you don’t want to miss the articles of the cafeteria, you can set the cafeteria as a star, so that it will appear in the top list of your official account. Set star method:

To improve page load speed, you can defer CSS and JavaScript resources by adjusting only the HTML code of the page. Delay CSS delayed media Delay JavaScript Resources such as CSS, fonts, and JavaScript are considered render-blocking . This means that the browser needs time to load page content before it actually renders them. So

1. Introduction to CORS for Cross-Origin Resource Sharing The entire CORS communication process is automatically completed by the browser and does not require user participation. The key to implementing CORS communication is the server. Cross-origin communication is possible as long as the server implements the CORS interface. The OPTIONS request is a preflight request ,

When I first entered the industry, I learned about macro tasks and micro tasks, which were also written in other people’s blogs. After working for more than a year, I have a little understanding of js! I went to understand the event loop, the task queue, and slowly it gave me the feeling that there

Hello everyone, I’m Fei Ge! Recently, I briefly studied the low-latency network architecture and shared it with you today. When it comes to an excellent low-latency network architecture, the first thing that comes to mind is the Internet giants, such as Tencent Alibaba Bytes. They always feel that the big companies must do the best.

The window.postMessage() method allows scripts from one document to pass text messages to scripts in another document, regardless of whether they are cross-domain or not. Scripts in one document still cannot call methods and read properties in other documents, but they can communicate securely using this messaging technique. This technique is called “Cross Document Messaging”,

js generates random numbers usually using the Math.random() function of javascript Several commonly used methods: Math.random() means: the result is between 0-1 (including 0, excluding 1); Math.floor(Math.random()*10+1) indicates that the result is a random number between 1-10 Math.floor(Math.random()*24) means the result is a random number between 0-23 1.Math.random(); returns a random number between 0-1, may

js to get two methods of custom attributes Four ways to get properties First get an element: var elem = document.getElementById(‘elem’); 1 1. Point (can not get custom attributes): 2. [] can also get attributes, which is beneficial for parameter transfer operations. elem.style[‘background’] = ‘yellow’ 1 3. getAttribute(): The early method of obtaining custom attributes.

This article mainly introduces the implementation of dragging and collision detection in js in detail. The sample code in the article is very detailed and has certain reference value. Interested friends can refer to it. The example in this article shares the specific code of js for dragging and collision detection for your reference. The

const getCookie = (name) => document.cookie.match(`[;\s+]?${name}=([^;]*)`)?.pop(); // For example, the cookie is as follows: a=b; c=d // use getCookie(‘c’) // d where match is the prototype method for strings. str.match(regexp) If a non-regex object is passed in, it is implicitly converted to a RegExp using new RegExp(obj) The above, so there is no need to