What is React?
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What is React?
How does React work under the hood?
What are some key advantages of building UIs with React?
What are some potential limitations or disadvantages of React?
What is JSX?
What is state in React?
What is the difference between state and props ?
What are React Hooks?
What benefits do React Hooks provide over class components ?
Can you show an example of a simple custom React Hook and why they are useful?
What are refs used for in React?
Why pass props to the super() constructor in React classes ?
How can you apply inline styling in React?
How do Class and Functional components differ in React?
How do Presentational and Container components differ in React?
What are Higher-Order Components in React and how are they useful?
What does it mean for a React component to be mounted ?
Walk through what happens when you call setState() in React
Why pass a callback function to setState() in React?
How does the useState() hook work in React?
What is the purpose of the Context API in ReactJS and when is it useful?
What problem do Fragments solve in React?
How can you ensure a function runs only once with useEffect() in React?
What role do props play in React components?
When and why are refs useful in React?
What's the difference between a Controlled component and an Uncontrolled one in React?
When rendering a list what is a key and what is its purpose?
What is the typical way to create and use refs in React?
What are some characteristics of Stateful components in React?
What are some characteristics of Stateless components in React?
What problem do portals solve in React and when would you use them?
How are Components and Containers different in Redux?
How can you use inline conditional expressions in ReactJS?
What is the Reconciliation process in ReactJS?
How are Elements and Components different in ReactJS?
What are some ways to access DOM elements in React?
What are the main phases in the React component lifecycle ?
Why is directly modifying state a bad idea in React?
Why are keys useful and how should they be used when rendering lists in React?
What is Component Composition in React and why is it useful?
How are useState() and useReducer() different in React?
Are there any limitations of React Hooks compared to classes?
How do Pure Components in React improve performance?
What problem do Error Boundaries solve in React?
How does StrictMode help when developing React apps?
How can shouldComponentUpdate() improve React performance?
Can you explain the Flux pattern and how it relates to React?
What does the {this.props.children} prop allow you to do in React?
How can you prevent a React component from unnecessary rendering ?
What is the typical way to render a list of components from an array in React?
What does the typical data flow look like in a React + Redux app?
What are some limitations on what you should do inside the component render method in React?
What are some ways to correctly bind event handlers in React classes?
What is prop drilling and how can you avoid it in React?
What is the purpose of shouldComponentUpdate() in React?
How do forward refs work in React?
What does the spread syntax (...) do in React?
How are Shadow DOM and Virtual DOM different in React?
Why bind class methods and event handlers to this in React classes?
What are some benefits of using Stateless Functional Components in React?
Why does React use className instead of the HTML class attribute?
What does Lifting State Up mean in React?
How are useRef() and createRef() different in React?
What's the difference between React.createElement() and React.cloneElement() ?
What common mistake leads to functions being called incorrectly on each render?
How does React event handling differ from native HTML events ?
What are some downsides of using React Context ?
What does Batching mean in React and how does it improve performance?
Which class component lifecycle methods can be replaced by useEffect() ?
What are some ways to handle errors with Error Boundaries in function components?
When is it useful to use the useRef() hook in React?
What are some ways to pass data from child to parent in React?
What is the optional second callback argument that can be passed to setState() ?
How would you manually create this JSX element without using JSX ?
Can you spot two potential issues with the React component code shown?
How to rewrite this React class component code using hooks instead?
What might be problematic about handling state like this in React?
How does component initialization differ between constructor() and getInitialState() in React?
What are some ways to validate props in React components?
What are the key differences between Flux and MVC patterns?
Is it possible to force a component to re-render without setState() in React?
Why does React use Synthetic Events ?
How would you debug performance issues with slow component rendering in React?
What makes a component a Pure Functional one in React?
Why is it important to pass props to the super() constructor in React classes?
Why bind event handlers to this in React class components?
Why doesn't this.props.children.map() work as expected in React?
How could you create a Props Proxy in a React higher order component?
What are some ways to conditionally render attributes in React components?
Does React re-render all components when setState() is called?
How does React handle events differently than regular DOM events ?
In what cases might you use the StrictMode component in React?
When should you use useCallback() , useMemo() and useEffect() in React components?
Is true inheritance possible between components in React?
How do Incremental DOM and Virtual DOM differ in React?
When might you need to use ReactDOM.flushSync() ?
When is the useReducer() hook useful in React?
How to store non-reactive state in React function components?
If you rendered a Twitter React element like below, how might the Twitter component be implemented?
Is there anything potentially wrong or suboptimal about this use of React's setState() ?
How can you prevent multiple re-renders when using several useState() hooks?
How does React as a UI library differ from Angular as a framework ?
What are some differences between Flux and AngularJS approaches?
What does React Fiber aim to improve?
How can you avoid the need for binding in React class components?
How and why would you use React.memo() ?
Is it a good idea for custom React hooks to return JSX ?
What is the order of execution of useInsertionEffect() , useEffect() , and useLayoutEffect() ?
How could you optimize this component with slow list filtering using a React Hook ?
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