If you want to import just the Component from the React library, what syntax do you use?
☑️ import React.Component from 'react'
☑️ import [ Component ] from 'react'
☑️ import Component from 'react'
✅ import { Component } from 'react'
If a function component should always render the
same way given the same props, what is a simple performance optimization available for it?
✅ Wrap it in the React.memo higher-order component.
☑️ Implement the useReducer Hook.
☑️ Implement the useMemo Hook.
☑️ Implement the shouldComponentUpdate lifecycle method.
How do you fix the syntax error that results from running this code?
const person =(firstName, lastName) =>
{
first: firstName,
last: lastName
}
console.log(person("Jill", "Wilson"))
✅ Wrap the object in parentheses.
☑️ Call the function from another file.
☑️ Add a return statement before the first curly brace.
☑️ Replace the object with an array.
If you see the following import in a file, what is being used for state management in the component?
import React, {useState} from 'react';
✅ React Hooks
☑️ stateful components
☑️ math
☑️ class components
Using object literal enhancement, you can put values back into an object. When you log person to the console, what is the output?
const name = 'Rachel';
const age = 31;
const person = { name, age };
console.log(person);
☑️ {{name: "Rachel", age: 31}}
✅ {name: "Rachel", age: 31}
☑️ {person: "Rachel", person: 31}}
☑️ {person: {name: "Rachel", age: 31}}
What is the testing library most often associated with React?
☑️ Mocha
☑️ Chai
☑️ Sinon
✅ Jest
To get the first item from the array ("cooking") using array destructuring, how do you adjust this line?
const topics = ['cooking', 'art', 'history'];
☑️ const first = ["cooking", "art", "history"]
☑️ const [] = ["cooking", "art", "history"]
☑️ const [, first]["cooking", "art", "history"]
✅ const [first] = ["cooking", "art", "history"]
How do you handle passing through the component tree without having to pass props down manually at every level?
☑️ React Send
☑️ React Pinpoint
☑️ React Router
✅ React Context
What should the console read when the following code is run?
const [, , animal] = ['Horse', 'Mouse', 'Cat'];
console.log(animal);
☑️ Horse
✅ Cat
☑️ Mouse
☑️ undefined
What is the name of the tool used to take JSX and turn it into
createElement calls?
☑️ JSX Editor
☑️ ReactDOM
☑️ Browser Buddy
✅ Babel
Top comments (1)
nice