JavaScript handles asynchronous operations like API calls, file reading, or timers using Promises and async/await. They help manage code that takes time to complete without blocking execution.

This blog explains promises and async/await with examples.

⭐ 1. What Is a Promise?

A Promise represents a value that may be available now, later, or never. It has three states:

Pending – initial state
Fulfilled – operation completed successfully
Rejected – operation failed

⭐ 2. Creating a Promise

const myPromise = new Promise((resolve, reject) => {
  let success = true;
  if(success){
    resolve("Operation successful!");
  } else {
    reject("Operation failed!");
  }
});

myPromise
  .then(result => console.log(result))
  .catch(error => console.log(error));

Output:

Operation successful!

⭐ 3. Chaining Promises

let promise = new Promise((resolve) => {
  resolve(5);
});

promise
  .then(result => result * 2)
  .then(result => result + 3)
  .then(result => console.log(result)); // 13

⭐ 4. Async/Await

async functions return a promise. await waits for the promise to resolve.

function fetchData() {
  return new Promise((resolve) => {
    setTimeout(() => resolve("Data fetched!"), 2000);
  });
}

async function getData() {
  let result = await fetchData();
  console.log(result);
}

getData(); // waits 2 seconds → "Data fetched!"

⭐ 5. Error Handling with Async/Await

Use try and catch to handle errors in async functions.

async function fetchData() {
  try {
    let result = await Promise.reject("Failed to fetch data");
  } catch(error) {
    console.log(error); // Failed to fetch data
  }
}

fetchData();

⭐ 6. Why Use Promises & Async/Await

Avoid callback hell
Handle asynchronous code cleanly
Improve readability and maintainability
Easier error handling

⭐ Conclusion

Promises and async/await are powerful tools for handling asynchronous operations in JavaScript. They make your code cleaner, readable, and easier to maintain while managing operations that take time to complete.

📌 Citations

🔗 View other articles about Javascript:
https://savanka.com/category/learn/js/

🔗 External Javascript Documentation:
https://www.w3schools.com/js/

JavaScript Promises And Async/Await Explained