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Saved Flashcards (3)
React Hooks
How do you correctly update state based on previous state in React?
Use a functional updater: `setCount(prev => prev + 1)`. This guarantees stale closure prevention during batch updates.
const [count, setCount] = useState(0); // Correct way: setCount(prev => prev + 1);
Next.js Route Handler
Where do you define REST API endpoints in Next.js App Router?
Inside `app/api/[route]/route.js` by exporting named async functions `export async function GET(request) {}`
// app/api/hello/route.js
import { NextResponse } from 'next/server';
export async function GET() {
return NextResponse.json({ message: 'Hello!' });
}Mongoose Querying
How to fetch only `title` and `author` while excluding `_id` in Mongoose?
Use `.select('title author -_id')` or `.select({ title: 1, author: 1, _id: 0 })`
const result = await Article.find().select('title author -_id');Saved Tutorials (2)
reactjs
1. Introduction to React & JSX
What is React, Virtual DOM, and how JSX transforms HTML inside JavaScript.