Q151. What is callback in callback?
You can nest one callback inside in another callback to execute the actions sequentially one by one. This is known as callbacks in callbacks. Beware, too many levels of n...
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Q152. What is a custom server in Next.js?
A way to customize the server-side behavior, e.g., with Express. ```js import { createServer } from "http"; import { parse } from "url"; import next from "next"; const po...
Q153. What is promise chaining?
The process of executing a sequence of asynchronous tasks one after another using promises is known as Promise chaining. Let's take an example of promise chaining for cal...
Q154. How to pretty print JSON with React?
We can use `` tag so that the formatting of the `JSON.stringify()` is retained: ```jsx harmony const data = { name: "John", age: 42 }; function User { return {JSON.string...
Q155. How do you perform client-side data fetching in Next.js?
Using `useEffect` and fetch or any other data fetching library like `axios`,`fetch` or `swr` by Next.js team. ``` import { useState, useEffect } from "react"; function Pr...
Q156. What is promise.all?
`Promise.all()` is a built-in JavaScript method used to handle multiple asynchronous operations together. It accepts an iterable of promises (usually an array) and return...
Q157. How do you set up GraphQL in Next.js?
By installing Apollo Client or any other GraphQL client and configuring it in the \_app.js file. ```bash npm install @apollo/client graphql yarn add @apollo/client graphq...
Q158. Does Promise.all() cancel the other Promises?
No. `Promise.all()` does not cancel the other promises. It only waits for all of them to finish, and if any one rejects, the overall `Promise.all()` call rejects immediat...
Q159. How to focus an input element on page load?
You need to use `useEffect` hook to set focus on input field during page load time for functional component. ```jsx harmony import React, { useEffect, useRef } from "reac...
Q160. How do you create API endpoints in Next.js?
Next.js provides built-in serverless backend capabilities for creating REST or GraphQL endpoints: ### 1. In App Router (Route Handlers - Modern): Create a `route.ts` (or ...