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Oct 7, 2024 · async/await builds on promises — for example, doSomething() is the same function as before, so there's minimal refactoring needed to change from promises to async/await. You can read more about the async/await syntax in the async functions and await references.
A JavaScript Promise object can be: The Promise object supports two properties: state and result. While a Promise object is "pending" (working), the result is undefined. When a Promise object is "fulfilled", the result is a value. When a Promise object is "rejected", the result is an error object.
Jun 13, 2023 · This article is an in-depth guide to promises in JavaScript. You are going to learn why JavaScript has promises, what a promise is, and how to work with it. You are also going to learn how to use async/await—a feature derived from promises—and what a job queue is. Here are the topics we will cover: Why should you care about promises?
Mar 14, 2020 · Here's how you might do with normal js... let element = document.getElementById('myid') element.addEventListener('change', ajaxModifyStatus) // Or... element.addEventListener('change', async() => { let result try { result = await ajaxModifyStatus() } catch (err) { console.log(err) } // Do something with result...
Jul 25, 2024 · The promise chain is what you need when your operation consists of several asynchronous functions, and you need each one to complete before starting the next one. But there are other ways you might need to combine asynchronous function calls, and the Promise API provides some helpers for them.
Sep 8, 2023 · A promise can be in one of three states: pending, fulfilled, or rejected. When a promise is pending, it means that the asynchronous operation is still in progress. When a promise is fulfilled, it means that the asynchronous operation has completed successfully.
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Feb 13, 2024 · Table of Contents. What is a Promise? Comparing Promises to Other Async Patterns. How to Create a Promise. How to Get the Result of a Promise. How to Handle Errors with then. Promise Chaining. How to Create Immediately Fulfilled or Rejected Promises. How to Use async and await. Promise Anti-Patterns. Summary. What is a Promise?
