React.js Developer Questionnaire Welcome to your React.js Questionnaire The questionnaire needs to be completed in 30 minutes. Full Name Email Address English Fluency Assessment > This general assessment has been designed to help us decide what level of fluency you possess in English, which is essential for all communication. I'm from Pune. ____________ is in Maharastra. They It He She Excuse Me. How _________ your last name? K-A-R-A-N Spell you spell do you spell spell you I'd like ________ omelette, please. A __ an two My name's Pete and this is Sylvia. ________ doctors from France. I'm We're She's They're Sorry, ________ Vaibhav. My name's Aman. I isn't I is not I aren't I 'm not I go to work ________ train. With by for in She ________ a dog. not have don't have don't has doesn't have Stephan ________ in our company. Work works is work working ________ they live in London? Are Is Do Does When do you play tennis? ________ Mondays. On In At By What time ________ work? starts he do he starts does he starts does he start ________ two airports in the city. It is There is There are This is ________ at school last week? Do you were Was you Were you You were Brad Pitt is a popular actor but I don't like ________ . him his her them We ________ the film last week. see saw sees were see He ________ tennis with me yesterday. doesn't played didn't played not played didn't play She was born ________ May 6th, 1979. in at on from Where ________ last summer? you went did you went do you went did you go Were you at the shop at 5 p.m. yesterday? No, I ________ . didn't am not wasn't weren't Excuse me, ________ is the T-shirt? It's 699/- what expensive how much how many how price React.js Developer Questionnaire > These questions are to assess your knowledge as a React.js Developer. Which of the following method does not represent the non-mutation? Concat() Method Reverse() Method Splice() Method None of the above Select the appropriate location for inclusion of a React common header component In the App index.html Inside every component separately In the gulpfile.js Only once in the App's index.js Which attribute set the text direction? dir lang direction sub What shows in the paragraph when a user clicks the button? class MyButton extends React.Component { constructor() { super(); this.state = { x: 5 }; } render() { return ( {this.state.x} click me ); } handleClick = () => { this.state.x = 10; }}ReactDOM.render(, document.getElementById("root")); 5 10 undefined throws an error Which React object name sets up the application routes SetRoute Route Reroute AddRoute Which feature related to data flow is provided by Flux, post-installation Two way binding Three way binding Directional data flow Unidirectional data flow In JavaScript what does x===y statement implies? Both x and y are equal in value, type and reference address as well Both are equal in the value and data type Both are x and y are equal in value only Both are not same at all Which is not valid data type in Javascript? Undefined Boolean Float Number What is the output? int a==2;int b=4;int ans=a+b;print(ans); 2 6 error 0 What will the following code output to the console when a user clicks the button? class MyButton extends React.Component { state = { a: 5, b: 10, c: 15 }; render() { return ( click me ); } handleClick = () => { this.setState({ a: 20, c: 25 }); console.log(this.state); }}ReactDOM.render(, document.getElementById("root")); {a: 20, b: 10, c: 25} {a: 20, c: 25} {a: 5, b: 10, c: 15} Which one of the following is correct output for the following code? var obj = { length:20, height:35,}if('breath' in obj === false) { obj.breadth = 12;}console.log(obj.breadth); Error Undefined 12 20 What will be the output of the following code? function getHeightType() { var height = 123.56; var type = (height>=190)?"Taller":"Little short"; return type;}var heightType = getHeightType();console.log(heightType); 123.56 Taller 190 Little short Which of the following selector selects all elements of E that have the attribute attr that end with the given value? E[attr^=value] E[attr$=value] E[attr*=value] None of the above Which of the following selector selects an element that has no children? :empty :nochild :inheritance :no-child What shows in console when a user clicks the button? class MyButton extends React.Component { state = { x: 1, y: 2 }; render() { return ( click me ); } handleClick = () => { this.setState({ x: 10, y: 20 }, () => { console.log(this.state); }); }}ReactDOM.render(, document.getElementById("root")); {x: 1, y: 2} {x: 10, y: 20} nothing throws an error Which of the following selectors selects adjacent siblings? E > F E F E + F E ~ F What will be the output of below mentioned code snippet? p strong {background-color: yellow;} Strong have yellow background Strong element within a p element have a yellow background Both p and strong have yellow background None of the above Review the following JavaScript code and pick the correct options: Assume that the API returns a successful 200 response code and a JSON object as the response body. const axios = require("axios");async function getData() { const result = await axios.get( "https://api.coindesk.com/v1/bpi/currentprice.json" ); return result;}let a = [];for (let i = 0, i < 10, i++) { const result = getData(); a.push(result);}console.log(a); Array a will be null or undefined Array a will be a JS object with the data returned by the API request Array a will contain promises Array a will be empty How do you access a function getData() from a h1 element in JSX? {getData()} ${getData()} {getData} ${getData} Considering the code below, how many times will the 'Hello' message be displayed on the console? const App = (props) => { const [counter, setCounter] = useState(0); useEffect( () => { console.log('Hello'); setCounter(1); }, [props.visible] ); return {counter};}; 0 1 2 3 Which method in a React Component should you override to stop the component from updating? willComponentUpdate shouldComponentUpdate componentDidUpdate componentDidMount 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 The CSS property used to set the distance between the borders of the adjacent cells in the table is border-collapse border-radius border-spacing None of the above Which of the following is the correct syntax to select the p siblings of a div element? Add description here! p div + p div p div ~ p The primary purpose of the array map() function is that it passes each element of the array and returns the necessary mapped elements passes each element of the array on which it is invoked to the function you specify, and returns an array containing the values returned by that function maps the elements of another array into itself None of the above When might you use React.PureComponent? when you do not want your component to have state when you have sibling components that need to be compared when you want a default implementation of shouldComponentUpdate() All of the above Which if the following CSS function allows us to perform calculations? calc() function calculator() function calculate() function cal() function What will happen if we execute the following code of JavaScript? vartensquared=(function(x){return x*x;}(10)); Memory leak Error Exception will be thrown Will work perfectly If the following lines of code differ, what is the difference? Code A !!(obj1 && obj2); Code B (obj1 && obj2); The first line results in a realBoolean value whereas the second line merely checks for the existence of the objects Both the lines of code A and B will result in a Boolean value "False" Both the lines of code A and B will check just for the existence of the object alone Both the lines of code A and B will result in a Boolean value "True" What will be the correct output of the following JavaScript code - Math.atan2(8,4)? 1.01 1.10 1.05 1.11 The CSS property used to specify the order of flex item in the grid container is order property float property overflow property None of the above What is a mixin? Mixins allow us to write pluggable and reusable functionalities for components Mixins will get execution precedence over the component’s own hooks Mixins can be simply reference it in multiple component. All of the above None of the above What should the console read when the following code is run? const [, , animal] = ['Horse', 'Cow', 'Cat']; console.log(animal); Horse Cow Cat Error