JavaScript Async...Await
About JavaScript Async/Await
Async/await is a modern way to handle asynchronous operations in JavaScript.
async and await simplify working with asynchronous code, especially promises.
They make asynchronous code look and behave like synchronous code, improving readability and reducing callback nesting.
Prerequisites
- Basic JavaScript knowledge
- Understanding of promises (helpful but not required)
async keyword
- The async keyword is used to declare an asynchronous function.
- An async function always returns a promise, even if you return a non-promise value.
await keyword
- The await keyword is used inside an async function to pause execution until the promise resolves or rejects.
Simple Async Function
The following is a simple example of a simple async function that returns a promise:
Async Function with Await
The following is a simple example of an async function with await.
Async Function With Fetch
The following is an example of async function with fetch. The fetch function is used to make HTTP requests and returns a promise that resolves to the response of the request.
try...catch is used to handle any errors that may occur during the fetch operation. If the fetch request fails, the error will be caught and logged to the console.
Async Arrow Function With Fetch
You can use async/await with arrow functions as well. Arrow functions provide a more concise syntax for writing functions, and they can also be declared as async functions.
The following is an example of async arrow function with fetch. The fetch function is used to make HTTP requests and returns a promise that resolves to the response of the request.
JavaScript Compiler For Live Practice
Practice the above JavaScript code in the following JavaScript Compiler. Create more Promises in the following editor and click Execute button to check the output. The output will be displayed in JavaScript Code Output section.
JavaScript Compiler