Fetch

Question 1

What does fetch( ) return?

Answer 1

A Promise

The Fetch API provides a JavaScript interface for accessing and manipulating parts of the protocol, such as requests and responses. It also provides a global fetch( ) method that provides an easy, logical way to fetch resources asynchronously across the network.

Question 2

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

Answer 2

Fetch takes two arguments, the “URL” and an object, “options”. Only the ‘URL’ is mandatory, and the method is set to GET by default if not provided.

Question 3

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

Answer 3

You would pass an object as the second argument for fetch, and the method would be in that object

i.e.

fetch(url, {GET})

fetch(url, {
method: “GET”, // POST, PUT, DELETE, etc.
headers: {
// the content type header value is usually auto-set
// depending on the request body
“Content-Type”: “text/plain;charset=UTF-8”
}

Question 4

When does React call a component’s componentDidMount method?

Answer 4

Right after the first time render( ) is called

Question 5

Name three React.Component lifecycle methods.

Answer 5

constructor, render, componentDidMount

Question 6

How do you pass data to a child component?

Answer 6

When you need to pass data from a parent to child class component, you do this by using props.