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Difference between EventEmitter and Observables in Node.js

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Difference between EventEmitter and Observables in Node.js

Difference between EventEmitter and Observables (in node js) is a Node.js topic. In plain words you use it for notify ‘saved’ in a small service. Don’t start with a slogan — start with that picture.

Smallest example: emitter.on / emit. Type it, run it, and say what you see. If you can do that from memory, you know Difference between EventEmitter and Observables (in node js).

From the example next to this theory — Difference between EventEmitter and Observables in Node.

Trap — too many listeners warning ignored. Fix that before you talk about advanced Node.js.

Viva: what is Difference between EventEmitter and Observables (in node js)? Then show emitter.on / emit. Then name the trap.

Exam tip

What is Difference between EventEmitter and Observables (in node js)? Show this: emitter.on / emit. Trap: too many listeners warning ignored.

Example

// Difference between EventEmitter and Observables in Node.js
const users = [
  { id: 1, name: "Asha" },
  { id: 2, name: "Ravi" },
];

function findUser(id) {
  return users.find((u) => u.id === id) ?? null;
}

console.log(findUser(2));
console.log(users.map((u) => u.name));

Difference between EventEmitter and Observables in Node.js: find user 2, then list names. Say both prints.

Short notes

DefDifference between EventEmitter and Observables (in node js) — notify ‘saved’ in a small service.
Ruleemitter.on / emit
Traptoo many listeners warning ignored
Usea small service

// Difference between EventEmitter and Observables in Node.js const users = [ { id: 1, name: "Asha" }, { id: 2, name: "Ravi" }, ]; function findUser(id) { return users.find((u) => u.id === id) ?? null; } console.log(findUser(2)); console.log(users.map((u) => u.name));

Difference between EventEmitter and Observables in Node.js

Example

Short notes

Questions

Difference between EventEmitter and Observables in Node.js

Example

Short notes

Questions