Q291. Can You Use Multiple Contexts in One Component?
Yes, it is possible. You can use multiple contexts inside the same component by calling useContext multiple times, once for each context. It can be achieved with below st...
Technical Question Bank · Peer-Reviewed
Job Interview Questions and Answers Directory
Search and filter frequently asked interview questions across technical, programming, and behavioral domains. Tailor your interview preparation by difficulty for freshers or experienced developers (454 available).
Active:
Tag: react ×
Q292. What's a common pitfall when using useContext with objects?
A **common pitfall** when using `useContext` with objects is **triggering unnecessary re-renders** across all consuming components — even when only part of the context va...
Q293. What would the context value be for no matching provider?
When a component calls `useContext(SomeContext)` but **no matching** `` **is present higher up in the component tree**, the **default value** passed to `React.createConte...
Q294. How do reactive dependencies in the useEffect dependency array affect its execution behavior?
The `useEffect` hook accepts an optional dependencies argument that accepts an array of reactive values. The **dependency array** determines **when** the effect runs. i.e...
Q295. When and how often does React invoke the setup and cleanup functions inside a useEffect hook?
1. **Setup Function Execution (`useEffect`)** The setup function (or the main function) you pass to `useEffect` runs at specific points: 1. **After the component is mount...
Q296. What happens if you return a Promise from useEffect??
You should NOT return a Promise from useEffect. React expects the function passed to useEffect to return either nothing (undefined) or a cleanup function (synchronous fun...
Q297. Can you have multiple useEffect hooks in a single component?
Yes, multiple useEffect hooks are allowed and recommended when you want to separate concerns. ```jsx useEffect(() => { // Handles API fetch }, []); useEffect(() => { // H...
Q298. How to prevent infinite loops with useEffect?
Infinite loops happen when the effect updates state that’s listed in its own dependency array, which causes the effect to re-run, updating state again and so on. **Infini...
Q299. What are the usecases of useLayoutEffect?
You need to use `useLayoutEffect` when your effect **must run before the browser paints**, such as: * **Reading layout measurements** (e.g., element size, scroll position...
Q300. How does useLayoutEffect work during server-side rendering (SSR)?
The `useLayoutEffect` hook does **not run on the server**, because there is no DOM. React issues a warning in server environments like Next.js if `useLayoutEffect` is use...