React JS Quiz

Welcome to your React JS Assessment

Name

Phone Number

1.React is a ________

A.Javascript library

B.Javascript framework

C.Both of above

D.None of above

ReactJS uses _____ to increase performance

A.Virtual DOM

B.Original DOM

C.Both of above

D.None of above

React is _______

A.Component based

B.Module based

C.Both of above

D.None of above

var Helloword=(props)=> { return( hello world 1 Hello world 2 ); } ReactDOM.render(,mountNode) What will be the output

A.Hello world 1

B.Hello world 2

C.Hello world 1 Hello world 2

D.Error

Number of elements, a valid react component can return

A.1

B.2

C.3

D.4

State in react is________

A.A permanent storage

B.Internal storage of the component

C.Both of above

D.None of above

In React JS, props can be used to pass

A.Properties to the component

B.Event handler to component

C.Both of above

D.None of above

The state in react can be updated by call to setState method. These calls are

A.Synchronous in nature

B.Asynchronous in nature

C.Are asynchronous but can be made synchronous when required

D.None of above

As soon as the state of react component is changed, component will

A.Does nothing , you have to call render method to render the component again

B.re-renders the component

C.be created again from scratch

D.None of above

10.

React Lifecycle method static getDerivedSateFromProps(props , state) is called when ____

A.Component is created for the first time

B.State of the component is updated

C.Both of above

D.None of above

11.

ComponentDidMount lifecycle method is called when____

A.Component is created for the first time

B.Component is updated

C.Both of above

D.None of above

12.

Keys are given to a list of elements in react. These keys should be

A.Unique in the DOM

B.Unique among components

C.Do not requires to be unique

D.None of above

13.

Everything in react is __________

A.module

B.component

C.package

D.class

14.

How many elements does a react component returns?

A.1

B.0

C.Multiple elements with one root element

D.None of the above

15.

Webpack command act as a _____________

A.module bundler

B.transpiler to transpile all javascript into 1 file

C.runs local dev server

D.none

16.

Reactjs is a _________

A.server side framework

B.user interface framework

C.library for building interaction interfaces

D.bundled jars

17.

What are two ways data gets handled in react?

A.state & props

B.services & components

C.state & services

D.state & component

18.

In react, this is used to pass data to component from outside?

A.set state

B.render with argument

C.props

D.propTypes

19.

React Js is developed by

A.Google

B.Microsoft

C.Facebook

D.None of above

20.

JSX is acronym for

A.Java Server eXtension

B.JavaScript eXtension

C.Java Script Extender

D.None of above

21.

Regarding React js components, which of following statement is true?

A.function components can have state

B.function components are light weight

C.class components are light weight

D.class components are faster than function component

22.

Regarding React js events, Which statement is true ?

A.Event raised in parent component can be handled in child component

B.Event raised in by child component can be handled in parent component

C.Event raised by a component can be handled only in that component

D.All of above

23.

In relation to React js component lifecycle, which statement is true

A.only function component can have life cycle

B.Only class components can have life cycle

C.Both type of components can have life cycle

D.None of above

24.

Which of the following API is a MUST for every ReactJS component?

A. getInitialState

B. render

C. renderComponent

D. None

25.

What are the advantages of React JS?

A. React can be used on client and as well as server side too

B. Using React increases readability and makes maintainability easier. Component, Data patterns improves readability and thus makes it easier for manitaining larger apps

C. React can be used with any other framework (Backbone.js, Angular.js) as it is only a view layer

D. All of the above

26.

Props are __________ into other components.

A. Injected

B.Methods

27.

In which directory react components are saved?

A. Inside vendor/

B.Inside js/components/

C.Inside vendor/components/

D.Inside external/components/

28.

What create-react-app command do

A. Update a react app

B.Creates new react app

C.install dependencies

29.

For what "webpack" command is used?

A. Transpiles all the Javascript down into one file

B.Runs react local development server.

C.A module bundler

30.

What function allows you to render React content in an HTML page?

A. React.mount()

B.ReactDOM.start()

C.ReactDOM.render()

D.React.render()

31.

React supports all the syntax of ........

A. ES6

B.C#

C.Native Java

D.None of the above

32.

Which of the following is the correct data flow sequence of flux(Redux) concept?

A. Action->Dispatcher->View->Store

B.Action->Dispatcher->Store->View

C.Action->Store->Dispatcher->View

D.None of the above

33.

The method useEffect() can be used in ----------------------component

A.functional component

B.class component

C.pure component

D.all the above

34.

Redux is used for ------------------------------

A.lifecycle hooks

B.state management

C.api call

35.

The method to be used for Router to implement?

A.BrowserRouter

B.WithRouter

C.PathLink

D.None of above

36.

How to Route the component with Router syntax?

37.

The method used to navigate between react router?

B.href

C.Link

38.

React is ----------------Application

A.Multipage Application

B.Single Page Application

C.Dual Page Application

D.All of the above

39.

To maintain state in functional component ----------------method to import

A.setState

B.useState

C.updateState

D.otherState

40.

IS nodejs to be needed while developing Reactjs application during development environment?

A.Yes

B.NO