asynchronous javascript tutorial

As you may know, the execution environment of Javascript is "single thread ). A single thread means that only one task can be completed at a time. If there are multiple tasks, you must queue up, complete the previous task, and then execute the next task, and so on. The advantage of this mode is that the implementation is relatively simple, and the execution environment is relatively simple. The disadvantage is that as long as one task takes a long tim

As you may know, the execution environment of Javascript is "single thread ). A single thread means that only one task can be completed at a time. If there are multiple tasks, you must queue up, complete the previous task, and then execute the next task, and so on. The advantage of this mode is that the implementation is relatively simple, and the execution environment is relatively simple. The disadvantage is that as long as one task takes a long tim

As you may know, the execution environment of Javascript is "single thread ).A single thread means that only one task can be completed at a time. If there are multiple tasks, you must queue up, complete the previous task, and then execute the next task, and so on.The advantage of this mode is that the implementation is relatively simple, and the execution environment is relatively simple. The disadvantage is that as long as one task takes a long time,

This article summarizes four methods of programming in quot; asynchronous mode quot, understanding them will allow you to write Javascript programs with a more reasonable structure, better performance, and more convenient maintenance. You may know that the execution environment of the Javascript language is "single thread ). A single thread means that only one

Introduction to asynchronous Macrotask and Microtask in JavaScriptWhat is Macrotask? What is Microtask?In understanding what is Macrotask? Before we take a look at the event looping mechanism in JavaScript, let's look at the following code: MicrotaskConsole.log (1); setTimeout(function() { Console.log (20); Console.log ( 3);It is obvious that the result of the above operation is 1,3,2;The above code settim

Asynchronous from setTimeout and setInterval to AJAX in JavaScript, setintervalajax SetTimeout and setInterval First, let's take a look at the following code to print the result. console.log(1);setTimeout(function() { console.log(2); },100)setTimeout(function() { console.log(3); },50)console.log(4); The print result is 1, 4, 3, and 2. You may think it is appropriate. Let's look at the example below. console

Building an application will always face asynchronous calls, whether in the Web front-end interface or the Node.js server, where JavaScript processing asynchronous calls is a disgusting thing. Previously only through the callback function, and then gradually evolved a lot of programs, and finally Promise to simple, easy to use, compatibility good win, but there a

that this await can only be async used in methods, so in order to use await a async main method that must be defined and called in the global scope. Because the Main method is asynchronous (declared as async), if main() there are other statements after the call, for example console.log("hello") , then this sentence will be executed first.Async/await syntax makes asynchronous calls write like synchronous co

Asynchronous programming in Javascript is gradually accepted by everyone. Previously, it was generally implemented through callback nesting, setTimeout, setInterval, and other methods. The code looks very inintuitive and difficult to understand without looking at the entire code logic. Asynchronous functions in Javascript