JavaScript Async/Await — Asaan Tarike Se

Agar aap JavaScript seekh rahe ho, to async/await wo cheez hai jo har developer ko aani chahiye. Aaj hum is ko bilkul beginner-friendly tareeke se samjhenge.

Pehle Synchronous vs Asynchronous Samjho

Synchronous code: Ek line khatam hone ke baad doosri chalti hai (jaise queue mein khade log).

Asynchronous code: Ek kaam shuru karke, jawab ka wait kiye baghair, doosre kaam pe chale jao (jaise tea order karke phone check karna).

Promise Kya Hota Hai?

Promise ek vada hai — ya to wo "fulfilled" hoga (kaam hogaya) ya "rejected" hoga (kaam fail).

const myPromise = fetch("https://api.example.com/data");

Async/Await Ka Jadu

async/await Promise ko synchronous jaisa likhne deta hai. Pehle dekho purana tareeqa:

fetch("/api/users")
  .then(res => res.json())
  .then(data => console.log(data))
  .catch(err => console.error(err));

Ab async/await ke saath:

async function getUsers() {
  try {
    const res = await fetch("/api/users");
    const data = await res.json();
    console.log(data);
  } catch (err) {
    console.error(err);
  }
}

Kitna clean aur readable hai!

Important Rules

1. await sirf async function ke andar use kar sakte ho
2. try/catch ka istemal must hai error handling ke liye
3. await line ke baad ka code wait karega

Real Example

async function loadUserProfile(userId) {
  const user = await fetch(`/api/users/${userId}`);
  const posts = await fetch(`/api/posts?user=${userId}`);
  return { user, posts };
}

Conclusion

async/await JavaScript mein asynchronous code likhne ka modern aur clean tareeqa hai. Practice karte raho — jaldi master ho jayega!

Agle post mein hum Promise.all() aur parallel requests sikhenge. 🚀