JavaScript Promises

Gain insights into JavaScript Promises to handle asynchronous events, chain multiple promises, utilize built-in methods, and master async functions with await expressions for efficient event handling.

Intermediate

40 Lessons

12h

Certificate of Completion

AI-POWERED

Explanations

AI-POWERED

Explanations

This course includes

69 Playgrounds

5 Quizzes

This course includes

69 Playgrounds

5 Quizzes

Course Overview

Promises are used to deal with event handling and callbacks in asynchronous programming in JavaScript, such as clicks and key presses. Promises allow developers to specify a function to execute at some later point in response to certain events. Promises may also indicate whether a certain code succeeded or failed in performing its assigned job. In this course, you will learn how to chain different promises, which makes the code easier to understand and debug. Next, you’ll learn built-in methods to monitor ...Show More

What You'll Learn

An in-depth understanding of JavaScript promises

An understanding of the asynchronous programming in JavaScript

Hands-on experience creating settled and unsettled promises

A working knowledge of chaining promises

Familiarity with monitoring and responding to promises executing in parallel

The ability to track unhandled rejections

What You'll Learn

An in-depth understanding of JavaScript promises

Course Content

Introduction

Get familiar with JavaScript promises, enhancing asynchronous programming and improving code clarity.

What’s This Course About?

Introduction to JavaScript Promises

Basics of Promises

Unpack the core of JavaScript promises, their states, handlers, and construction methods.

Fundamentals of Promises Handlers Handlers Executed as Microtasks Unsettled Promises Settled Promises Non-Promise Thenables Summary: Basics of Promises Quiz: Basics of Promises

Chaining Promises

Examine JavaScript promise chaining to handle sequential async operations and centralized error management.

Fundamentals of Chaining Promises Promise Chains with the finally() Method Return Values in Promise Chains Return Promises in Promise Chains Return Promises from finally()Summary: Chaining Promises Quiz: Chaining Promises

Working with Multiple Promises

Grasp the fundamentals of managing multiple promises using Promise.all(), allSettled(), any(), and race().

The Promise.all() Method When to Use the Promise.all() Method The Promise.allSettled() Method When to Use the Promise.allSettled() Method The Promise.any() Method When to Use the Promise.any() method The Promise.race() Method When to Use Promise.race()Summary: Working with Multiple Promises Quiz: Working with Multiple Promises

Async Functions and Await Expressions

Take a closer look at async functions, await expressions, and promise handling in JavaScript.

Async Functions What Makes Async Functions Different?Await Expressions Await Expressions and Promises Await Expressions and Loops Summary: Async Functions and Await Expressions Quiz: Async Functions and Await Expressions

Tracking Down the Unhandled Rejections

5 Lessons

Focus on tracking and managing unhandled promise rejections across JavaScript environments.

Conclusion

1 Lesson

Build on key concepts of JavaScript promises, async/await, and error handling.

Course Author

Trusted by 1.4 million developers working at companies

Anthony Walker

@_webarchitect_

Emma Bostian 🐞

@EmmaBostian

Evan Dunbar

ML Engineer

Carlos Matias La Borde

Software Developer

Souvik Kundu

Front-end Developer

Vinay Krishnaiah

Software Developer

Eric Downs

Musician/Entrepeneur

Kenan Eyvazov

DevOps Engineer

Anthony Walker

@_webarchitect_

Emma Bostian 🐞

@EmmaBostian

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