promises

Question 1

What are the three states a Promise can be in?

Answer 1

pending - The initial state of a promise.
fulfilled - The state of a promise representing a successful operation.
rejected - The state of a promise representing a failed operation.

Question 2

How do you handle the fulfillment of a Promise?

Answer 2

use the .then method and then you pass in an anonymous arrow functions

Question 3

How do you handle the rejection of a Promise?

Answer 3

by calling the .catch( ) method, and take a function as its argument

Question 4

What doesfetch()return?

Answer 4

it return a Promise

Question 5

What is the default request method used by fetch()?

Answer 5

.get()

Question 6

How do you specify the request method (GET, POST, etc.) when calling fetch?

Answer 6

add a second parameter with request method

Question 7

When does React call a component’s componentDidMount method?

Answer 7

invoked immediately after a component is mounted or inserted into the tree. If you need to load data from a remote endpoint, this a good place to instantiate the network request.(after first successful render)

Question 8

Name three React.Component lifecycle methods.

Answer 8

mounting, updating, unmounting

Question 9

How do you pass data to a child component?

Answer 9

by using this.state.(__) in the parent component then this.prop.data in the child component