Readings

React Docs-Lists and Keys

What does .map() return?

If I want to loop through an array and display each value in JSX, how do I do that in React?

• takes an array of numbers and doubles their value.

Each list item needs a unique ____.

• key

What is the purpose of a key?

• Keys help React identify which items have changed, are added, or are removed.

The Spread Operator

What is the spread operator?

• adding items to arrays, combining arrays or objects, and spreading an array out into a function’s arguments.

List 4 things that the spread operator can do.

• copy an array, concentrating or combining arrays, une mathing functions, using an array as arguments.

Give an example of using the spread operator to combine two arrays.

• const oldArr1 = [1,2,3]; const oldArr2 = [4,5,6]; const newArr = […oldArr1,…oldArr2];

Give an example of using the spread operator to add a new item to an array.

• by adding ...oldArray to a new array.

Give an example of using the spread operator to combine two objects into one.

• combine objects 1 arr and 2 arr into a third array

Videos

How to pass Functions Between Components

In the video, what is the first step that the developer does to pass functions between components?

• create function increment and pass in person object

In your own words, what does the increment function do?

• it takes a vaiable and changes it value

How can you pass a method from a parent component into a child component?

• this.increment

How does the child component invoke a method that was passed to it from a parent component?

• I’m not really sure, this is not easy to understand

Bookmark and Review

React Tutorial through ‘Declaring a Winner’

React Docs-Lifting State Up

Things I want to know more about

• I want to read up on passing functions between comnponents. I watched the video a couple of times but didn’t exactly understand it