events Module & EventEmitter
EventEmitter, Node.js ke, EVENT-DRIVEN, ARCHITECTURE, ka, FOUNDATION, hai — MANY, Node.js, CORE, MODULES, (http, streams) EventEmitter, se, INHERIT, karte, hain. .on() se, EVENT, LISTEN, kiya, jaata, hai, .emit() se, EVENT, TRIGGER, kiya, jaata, hai.
EK, HI, EVENT, PAR, MULTIPLE, LISTENERS, ATTACH, kiye, ja, sakte, hain — SAB, LISTENERS, CALL, HOTE, HAIN, JIS, ORDER, mein, WOH, REGISTER, HUE, THE.
const EventEmitter = require("events");
class OrderEmitter extends EventEmitter {}
const orderEvents = new OrderEmitter();
orderEvents.on("order-placed", (order) => {
console.log("Sending confirmation email for order:", order.id);
});
orderEvents.on("order-placed", (order) => {
console.log("Updating inventory for order:", order.id);
});
orderEvents.emit("order-placed", { id: 42 });- EventEmitter = Node.js ke, event-driven architecture, ka, foundation
- .on() = listen karta hai, .emit() = event trigger karta hai
- Multiple listeners, EK, event, PAR, ATTACH, kiye, ja, sakte, hain
emit(), MULTIPLE, ARGUMENTS, PASS, kar, sakta hai — listener, function, mein, SAB, ARGUMENTS, ke, roop, mein, RECEIVE, hote, HAIN, EK, SINGLE, OBJECT, ki, JAGAH, (HALANKI, OBJECT, PASS, karna, EXTENSIBILITY, ke, liye, aksar, BEHTAR, hai).
emitter.on("order", (id, amount) => console.log(id, amount));
emitter.emit("order", 42, 199.99);AGAR, "error" EVENT, EMIT, hota hai, aur, KOI, LISTENER, REGISTERED, NAHI, hai, Node.js, EK, EXCEPTION, THROW, karके, PROCESS, ko, CRASH, kar, deta hai — YE, DESIGN, CHOICE, hai, TAAKI, ERRORS, SILENTLY, IGNORE, NA, HON.