Notice: This page requires JavaScript to function properly.
Please enable JavaScript in your browser settings or update your browser.
Aprende Creating a Basic Promise | Mastering Promises
Practice
Projects
Quizzes & Challenges
Quizzes
Challenges
/
Asynchronous JavaScript Explained

bookCreating a Basic Promise

script.js

script.js

index.html

index.html

copy

When you create a new Promise in JavaScript, it starts in the pending state. In the example above, the myPromise object is created using the Promise constructor, which takes a function with two arguments: resolve and reject. Inside this function, you can perform asynchronous operations. Here, a setTimeout is used to simulate a delay. After one second, the resolve function is called with the value "Promise fulfilled!". This action moves the promise from the pending state to the fulfilled state. Once the promise is fulfilled, any .then() handlers attached to the promise will execute, receiving the resolved value. This pattern allows you to write asynchronous code that is easier to read and manage than deeply nested callbacks.

question mark

What does the resolve function do in a Promise?

Select the correct answer

¿Todo estuvo claro?

¿Cómo podemos mejorarlo?

¡Gracias por tus comentarios!

Sección 2. Capítulo 2

Pregunte a AI

expand

Pregunte a AI

ChatGPT

Pregunte lo que quiera o pruebe una de las preguntas sugeridas para comenzar nuestra charla

Suggested prompts:

Can you explain what happens if the promise is rejected instead of resolved?

Can you show how to handle errors with promises?

What are some real-world use cases for using promises in JavaScript?

bookCreating a Basic Promise

Desliza para mostrar el menú

script.js

script.js

index.html

index.html

copy

When you create a new Promise in JavaScript, it starts in the pending state. In the example above, the myPromise object is created using the Promise constructor, which takes a function with two arguments: resolve and reject. Inside this function, you can perform asynchronous operations. Here, a setTimeout is used to simulate a delay. After one second, the resolve function is called with the value "Promise fulfilled!". This action moves the promise from the pending state to the fulfilled state. Once the promise is fulfilled, any .then() handlers attached to the promise will execute, receiving the resolved value. This pattern allows you to write asynchronous code that is easier to read and manage than deeply nested callbacks.

question mark

What does the resolve function do in a Promise?

Select the correct answer

¿Todo estuvo claro?

¿Cómo podemos mejorarlo?

¡Gracias por tus comentarios!

Sección 2. Capítulo 2
some-alt