| Core React | false | |
1 | What is React? | false | |
2 | What are the major features of React? | false | |
3 | What is JSX? | false | |
4 | What is the difference between Element and Component? | false | |
5 | How to create components in React? | false | |
6 | When to use a Class Component over a Function Component? | false | |
7 | What are Pure Components? | false | |
8 | What is state in React? | false | |
9 | What are props in React? | false | |
10 | What is the difference between state and props? | false | |
11 | Why should we not update the state directly? | false | |
12 | What is the purpose of callback function as an argument of setState()? | false | |
13 | What is the difference between HTML and React event handling? | false | |
14 | How to bind methods or event handlers in JSX callbacks? | false | |
15 | How to pass a parameter to an event handler or callback? | false | |
16 | What are synthetic events in React? | false | |
17 | What are inline conditional expressions? | false | |
18 | What is "key" prop and what is the benefit of using it in arrays of elements? | false | |
19 | What is the use of refs? | false | |
20 | How to create refs? | false | |
21 | What are forward refs? | false | |
22 | Which is preferred option with in callback refs and findDOMNode()? | false | |
23 | Why are String Refs legacy? | false | |
24 | What is Virtual DOM? | false | |
25 | How Virtual DOM works? | false | |
26 | What is the difference between Shadow DOM and Virtual DOM? | false | |
27 | What is React Fiber? | false | |
28 | What is the main goal of React Fiber? | false | |
29 | What are controlled components? | false | |
30 | What are uncontrolled components? | false | |
31 | What is the difference between createElement and cloneElement? | false | |
32 | What is Lifting State Up in React? | false | |
33 | What are the different phases of component lifecycle? | false | |
34 | What are the lifecycle methods of React? | false | |
35 | What are Higher-Order components? | false | |
36 | How to create props proxy for HOC component? | false | |
37 | What is context? | false | |
38 | What is children prop? | false | |
39 | How to write comments in React? | false | |
40 | What is the purpose of using super constructor with props argument? | false | |
41 | What is reconciliation? | false | |
42 | How to set state with a dynamic key name? | false | |
43 | What would be the common mistake of function being called every time the component renders? | false | |
44 | Is lazy function supports named exports? | false | |
45 | Why React uses className over class attribute? | false | |
46 | What are fragments? | false | |
47 | Why fragments are better than container divs? | false | |
48 | What are portals in React? | false | |
49 | What are stateless components? | false | |
50 | What are stateful components? | false | |
51 | How to apply validation on props in React? | false | |
52 | What are the advantages of React? | false | |
53 | What are the limitations of React? | false | |
54 | What are error boundaries in React v16 | false | |
55 | How error boundaries handled in React v15? | false | |
56 | What are the recommended ways for static type checking? | false | |
57 | What is the use of react-dom package? | false | |
58 | What is the purpose of render method of react-dom? | false | |
59 | What is ReactDOMServer? | false | |
60 | How to use InnerHtml in React? | false | |
61 | How to use styles in React? | false | |
62 | How events are different in React? | false | |
63 | What will happen if you use setState in constructor? | false | |
64 | What is the impact of indexes as keys? | false | |
65 | Is it good to use setState() in componentWillMount() method? | false | |
66 | What will happen if you use props in initial state? | false | |
67 | How do you conditionally render components? | false | |
68 | Why we need to be careful when spreading props on DOM elements?? | false | |
69 | How you use decorators in React? | false | |
70 | How do you memoize a component? | false | |
71 | How you implement Server-Side Rendering or SSR? | false | |
72 | How to enable production mode in React? | false | |
73 | What is CRA and its benefits? | false | |
74 | What is the lifecycle methods order in mounting? | false | |
75 | What are the lifecycle methods going to be deprecated in React v16? | false | |
76 | What is the purpose of getDerivedStateFromProps() lifecycle method? | false | |
77 | What is the purpose of getSnapshotBeforeUpdate() lifecycle method? | false | |
78 | Do Hooks replace render props and higher order components? | false | |
79 | What is the recommended way for naming components? | false | |
80 | What is the recommended ordering of methods in component class? | false | |
81 | What is a switching component? | false | |
82 | Why we need to pass a function to setState()? | false | |
83 | What is strict mode in React? | false | |
84 | What are React Mixins? | false | |
85 | Why is isMounted() an anti-pattern and what is the proper solution? | false | |
86 | What are the Pointer Events supported in React? | false | |
87 | Why should component names start with capital letter? | false | |
88 | Are custom DOM attributes supported in React v16? | false | |
89 | What is the difference between constructor and getInitialState? | false | |
90 | Can you force a component to re-render without calling setState? | false | |
91 | What is the difference between super() and super(props) in React using ES6 classes? | false | |
92 | How to loop inside JSX? | false | |
93 | How do you access props in attribute quotes? | false | |
94 | What is React PropType array with shape? | false | |
95 | How to conditionally apply class attributes? | false | |
96 | What is the difference between React and ReactDOM? | false | |
97 | Why ReactDOM is separated from React? | false | |
98 | How to use React label element? | false | |
99 | How to combine multiple inline style objects? | false | |
100 | How to re-render the view when the browser is resized? | false | |
101 | What is the difference between setState and replaceState methods? | false | |
102 | How to listen to state changes? | false | |
103 | What is the recommended approach of removing an array element in react state? | false | |
104 | Is it possible to use React without rendering HTML? | false | |
105 | How to pretty print JSON with React? | false | |
106 | Why you can't update props in React? | false | |
107 | How to focus an input element on page load? | false | |
108 | What are the possible ways of updating objects in state? | false | |
110 | How can we find the version of React at runtime in the browser? | false | |
111 | What are the approaches to include polyfills in your create-react-app? | false | |
112 | How to use https instead of http in create-react-app? | false | |
113 | How to avoid using relative path imports in create-react-app? | false | |
114 | How to add Google Analytics for react-router? | false | |
115 | How to update a component every second? | false | |
116 | How do you apply vendor prefixes to inline styles in React? | false | |
117 | How to import and export components using react and ES6? | false | |
118 | What are the exceptions on React component naming? | false | |
119 | Why is a component constructor called only once? | false | |
120 | How to define constants in React? | false | |
121 | How to programmatically trigger click event in React? | false | |
122 | Is it possible to use async/await in plain React? | false | |
123 | What are the common folder structures for React? | false | |
124 | What are the popular packages for animation? | false | |
125 | What is the benefit of styles modules? | false | |
126 | What are the popular React-specific linters? | false | |
127 | How to make AJAX call and In which component lifecycle methods should I make an AJAX call? | false | |
128 | What are render props? | false | |
| React Router | false | |
129 | What is React Router? | false | |
130 | How React Router is different from history library? | false | |
131 | What are the <Router> components of React Router v4? | false | |
132 | What is the purpose of push and replace methods of history? | false | |
133 | How do you programmatically navigate using React router v4? | false | |
134 | How to get query parameters in React Router v4 | false | |
135 | Why you get "Router may have only one child element" warning? | false | |
136 | How to pass params to history.push method in React Router v4? | false | |
137 | How to implement default or NotFound page? | false | |
138 | How to get history on React Router v4? | false | |
139 | How to perform automatic redirect after login? | false | |
| React Internationalization | false | |
140 | What is React-Intl? | false | |
141 | What are the main features of React Intl? | false | |
142 | What are the two ways of formatting in React Intl? | false | |
143 | How to use FormattedMessage as placeholder using React Intl? | false | |
144 | How to access current locale with React Intl | false | |
145 | How to format date using React Intl? | false | |
| React Testing | false | |
146 | What is Shallow Renderer in React testing? | false | |
147 | What is TestRenderer package in React? | false | |
148 | What is the purpose of ReactTestUtils package? | false | |
149 | What is Jest? | false | |
150 | What are the advantages of Jest over Jasmine? | false | |
151 | Give a simple example of Jest test case | false | |
| React Redux | false | |
152 | What is Flux? | false | |
153 | What is Redux? | false | |
154 | What are the core principles of Redux? | false | |
155 | What are the downsides of Redux compared to Flux? | false | |
156 | What is the difference between mapStateToProps() and mapDispatchToProps()? | false | |
157 | Can I dispatch an action in reducer? | false | |
158 | How to access Redux store outside a component? | false | |
159 | What are the drawbacks of MVW pattern | false | |
160 | Are there any similarities between Redux and RxJS? | false | |
161 | How to dispatch an action on load? | false | |
162 | How to use connect from React Redux? | false | |
163 | How to reset state in Redux? | false | |
164 | Whats the purpose of at symbol in the redux connect decorator? | false | |
165 | What is the difference between React context and React Redux? | false | |
166 | Why are Redux state functions called reducers? | false | |
167 | How to make AJAX request in Redux? | false | |
168 | Should I keep all component's state in Redux store? | false | |
169 | What is the proper way to access Redux store? | false | |
170 | What is the difference between component and container in React Redux? | false | |
171 | What is the purpose of the constants in Redux? | false | |
172 | What are the different ways to write mapDispatchToProps()? | false | |
173 | What is the use of the ownProps parameter in mapStateToProps() and mapDispatchToProps()? | false | |
174 | How to structure Redux top level directories? | false | |
175 | What is redux-saga? | false | |
176 | What is the mental model of redux-saga? | false | |
177 | What are the differences between call and put in redux-saga | false | |
178 | What is Redux Thunk? | false | |
179 | What are the differences between redux-saga and redux-thunk | false | |
180 | What is Redux DevTools? | false | |
181 | What are the features of Redux DevTools? | false | |
182 | What are Redux selectors and Why to use them? | false | |
183 | What is Redux Form? | false | |
184 | What are the main features of Redux Form? | false | |
185 | How to add multiple middlewares to Redux? | false | |
186 | How to set initial state in Redux? | false | |
187 | How Relay is different from Redux? | false | |
188 | What is an action in Redux? | false | |
| React Native | false | |
188 | What is the difference between React Native and React? | false | |
189 | How to test React Native apps? | false | |
190 | How to do logging in React Native? | false | |
191 | How to debug your React Native? | false | |
| React supported libraries and Integration | false | |
192 | What is reselect and how it works? | false | |
193 | What is Flow? | false | |
194 | What is the difference between Flow and PropTypes? | false | |
195 | How to use font-awesome icons in React? | false | |
196 | What is React Dev Tools? | false | |
197 | Why is DevTools not loading in Chrome for local files? | false | |
198 | How to use Polymer in React? | false | |
199 | What are the advantages of React over Vue.js? | false | |
200 | What is the difference between React and Angular? | false | |
201 | Why React tab is not showing up in DevTools? | false | |
202 | What are styled components? | false | |
203 | Give an example of Styled Components? | false | |
204 | What is Relay? | false | |
205 | How to use TypeScript in create-react-app application? | false | |
| Miscellaneous | false | |
206 | What are the main features of reselect library? | false | |
207 | Give an example of reselect usage? | false | |
209 | Does the statics object work with ES6 classes in React? | false | |
210 | Can Redux only be used with React? | false | |
211 | Do you need to have a particular build tool to use Redux? | false | |
212 | How Redux Form initialValues get updated from state? | false | |
213 | How React PropTypes allow different type for one prop? | false | |
214 | Can I import an SVG file as react component? | false | |
215 | Why are inline ref callbacks or functions not recommended? | false | |
216 | What is render hijacking in React? | false | |
217 | What are HOC factory implementations? | false | |
218 | How to pass numbers to React component? | false | |
219 | Do I need to keep all my state into Redux? Should I ever use react internal state? | false | |
220 | What is the purpose of registerServiceWorker in React? | false | |
221 | What is React memo function? | false | |
222 | What is React lazy function? | false | |
223 | How to prevent unnecessary updates using setState? | false | |
224 | How do you render Array, Strings and Numbers in React 16 Version? | false | |
225 | How to use class field declarations syntax in React classes? | false | |
226 | What are hooks? | false | |
227 | What are the rules needs to follow for hooks? | false | |
228 | How to ensure hooks followed the rules in your project? | false | |
229 | What are the differences between Flux and Redux? | false | |
230 | What are the benefits of React Router V4? | false | |
231 | Can you describe about componentDidCatch lifecycle method signature? | false | |
232 | In which scenarios error boundaries do not catch errors? | false | |
233 | Why do you not need error boundaries for event handlers? | false | |
234 | What is the difference between try catch block and error boundaries? | false | |
235 | What is the behavior of uncaught errors in react 16? | false | |
236 | What is the proper placement for error boundaries? | false | |
237 | What is the benefit of component stack trace from error boundary? | false | |
238 | What is the required method to be defined for a class component? | false | |
239 | What are the possible return types of render method? | false | |
240 | What is the main purpose of constructor? | false | |
241 | Is it mandatory to define constructor for React component? | false | |
242 | What are default props? | false | |
243 | Why should not call setState in componentWillUnmount? | false | |
244 | What is the purpose of getDerivedStateFromError? | false | |
245 | What is the methods order when component re-rendered? | false | |
246 | What are the methods invoked during error handling? | false | |
247 | What is the purpose of displayName class property? | false | |
248 | What is the browser support for react applications? | false | |
249 | What is the purpose of unmountComponentAtNode method? | false | |
250 | What is code-splitting? | false | |
251 | What is the benefit of strict mode? | false | |
252 | What are Keyed Fragments? | false | |
253 | Does React support all HTML attributes? | false | |
254 | What are the limitations with HOCs? | false | |
255 | How to debug forwardRefs in DevTools? | false | |
256 | When component props defaults to true? | false | |
257 | What is NextJS and major features of it? | false | |
258 | How do you pass an event handler to a component? | false | |
259 | Is it good to use arrow functions in render methods? | false | |
260 | How to prevent a function from being called multiple times? | false | |
261 | How JSX prevents Injection Attacks? | false | |
262 | How do you update rendered elements? | false | |
263 | How do you say that props are read only? | false | |
264 | How do you say that state updates are merged? | false | |
265 | How do you pass arguments to an event handler? | false | |
266 | How to prevent component from rendering? | false | |
267 | What are the conditions to safely use the index as a key? | false | |
268 | Is it keys should be globally unique? | false | |
269 | What is the popular choice for form handling? | false | |
270 | What are the advantages of formik over redux form library? | false | |
271 | Why do you not required to use inheritance? | false | |
272 | Can I use web components in react application? | false | |
273 | What is dynamic import? | false | |
274 | What are loadable components? | false | |
275 | What is suspense component? | false | |
276 | What is route based code splitting? | false | |
277 | Give an example on How to use context? | false | |
278 | What is the purpose of default value in context? | false | |
279 | How do you use contextType? | false | |
280 | What is a consumer? | false | |
281 | How do you solve performance corner cases while using context? | false | |
282 | What is the purpose of forward ref in HOCs? | false | |
283 | Is it ref argument available for all functions or class components? | false | |
284 | Why do you need additional care for component libraries while using forward refs? | false | |
285 | How to create react class components without ES6? | false | |
286 | Is it possible to use react without JSX? | false | |
287 | What is diffing algorithm? | false | |
288 | What are the rules covered by diffing algorithm? | false | |
289 | When do you need to use refs? | false | |
290 | Is it prop must be named as render for render props? | false | |
291 | What are the problems of using render props with pure components? | false | |
292 | How do you create HOC using render props? | false | |
293 | What is windowing technique? | false | |
294 | How do you print falsy values in JSX? | false | |
295 | What is the typical use case of portals? | false | |
296 | How do you set default value for uncontrolled component? | false | |
297 | What is your favorite React stack? | false | |
298 | What is the difference between Real DOM and Virtual DOM? | false | |
299 | How to add Bootstrap to a react application? | false | |
300 | Can you list down top websites or applications using react as front end framework? | false | |
301 | Is it recommended to use CSS In JS technique in React? | false | |
302 | Do I need to rewrite all my class components with hooks? | false | |
303 | How to fetch data with React Hooks? | false | |
304 | Is Hooks cover all use cases for classes? | false | |
305 | What is the stable release for hooks support? | false | |
306 | Why do we use array destructuring (square brackets notation) in useState? | false | |
307 | What are the sources used for introducing hooks? | false | |
308 | How do you access imperative API of web components? | false | |
309 | What is formik? | false | |
310 | What are typical middleware choices for handling asynchronous calls in Redux? | false | |
311 | Do browsers understand JSX code? | false | |
312 | Describe about data flow in react? | false | |
313 | What is react scripts? | false | |
314 | What are the features of create react app? | false | |
315 | What is the purpose of renderToNodeStream method? | false | |
316 | What is MobX? | false | |
317 | What are the differences between Redux and MobX? | false | |
318 | Should I learn ES6 before learning ReactJS? | false | |
319 | What is Concurrent Rendering? | false | |
320 | What is the difference between async mode and concurrent mode? | false | |
321 | Can I use javascript urls in react16.9? | false | |
322 | What is the purpose of eslint plugin for hooks? | false | |
323 | What is the difference between Imperative and Declarative in React? | false | |
324 | What are the benefits of using typescript with reactjs? | false | |
325 | How do you make sure that user remains authenticated on page refresh while using Context API State Management? | false | |
326 | What are the benefits of new JSX transform? | false | |
327 | How does new JSX transform different from old transform? | false | |
328 | How do you get redux scaffolding using create-react-app? | false | |
329 | What are React Server components? | false | |