Asynchronous JavaScript
Asynchronous JavaScript allows developers to handle tasks without blocking the main application flow. This evolution from callbacks and XMLHttpRequest to promises and async/await has improved user experience by keeping applications responsive. The article discusses the progression of asynchronous techniques in JavaScript and their significance in modern web development.
- ▪JavaScript code typically runs synchronously, but asynchronous JavaScript allows for non-blocking operations.
- ▪Callbacks and XMLHttpRequest were the primary methods for handling asynchronous tasks before the introduction of promises and async/await.
- ▪Callback hell occurs when multiple asynchronous tasks depend on each other, leading to deeply nested callbacks.
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try { if(localStorage) { let currentUser = localStorage.getItem('current_user'); if (currentUser) { currentUser = JSON.parse(currentUser); if (currentUser.id === 3442252) { document.getElementById('article-show-container').classList.add('current-user-is-article-author'); } } } } catch (e) { console.error(e); } Brendon O'Neill Posted on May 20 Asynchronous JavaScript #webdev #javascript #programming #learning When we write JavaScript or TypeScript, most of our code runs from top to bottom, line by line. This is what we usually think of as synchronous code. One line runs, then the next, then the next. But when we need to get information from a server, things are different. We cannot just freeze the whole application while we wait for that data to come back.
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