react-form-controls

Question 1

What are controlled components?

Answer 1

Form data that is controlled by the components state.

Question 2

What two props must you pass to an input for it to be “controlled”?

Answer 2

onChange and value

Question 3

What does setState do?

Answer 3

1. Updates the state, skipping properties not included in the object passed to setState
2. Calls the render() method

Question 4

What happens to the DOM in React and the browser on every render() call?

Answer 4

1. A new React DOM tree is made
2. The new one looks at the old one and finds what is different
3. The browser DOM page is patched based on those differences