Updating object using state

Question 1

Treat all state in React as immutable.

Question 2

When you store objects in state

Answer 2

mutating them will not trigger renders and will change the state in previous render “snapshots”.

Question 3

Instead of mutating an object

Answer 3

create a new version of it

Question 4

You can use the {…obj

Answer 4

something: ‘newValue’} object spread syntax to create copies of objects.

Question 5

Spread syntax is shallow: it only copies one level deep.

Question 6

To update a nested object

Answer 6

you need to create copies all the way up from the place you’re updating.

Question 7

To reduce repetitive copying code

Answer 7

use Immer.