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Practice

Async/Await Asynchronous Handling

async and await are syntax features in JavaScript that make asynchronous code easier and cleaner to manage.

Using promises with .then() and .catch() to continuously link callback functions can make the code complex and reduce readability.

async/await addresses these issues and allows you to write asynchronous code just like synchronous code.

Such asynchronous handling is commonly used when fetching data from external servers or storage, as these operations can be time-consuming.

An interface used for tasks such as retrieving data from or sending data to a server is known as an API.

API stands for Application Programming Interface, which refers to a set of rules for communication with a server.


async/await Example
async function fetchUserData() {
  try {
    // Fetch data from an external API using the fetch function
    const response = await fetch('https://api.example.com/user');

    // Parse as JSON
    const data = await response.json();

    // Output data
    console.log(data);
  } catch (error) {
    console.log('Failed to fetch data:', error);
  }
}

// Call function
fetchUserData();

In the example above, async is a keyword that declares an asynchronous function, and await is a keyword that waits for a promise to resolve before returning the result.

If there is an issue with the fetch call or data parsing, the catch block handles the error.


Features​

  1. Asynchronous Function: When you declare a function with async, it always returns a promise.

  2. Error Handling: Errors can be conveniently managed using try/catch blocks.


Food Order Example​

async/await can be used to illustrate waiting for food in a restaurant scenario.

  • async represents the act of taking an order as a function.

  • await waits for the food (Promise) to be ready in async.

  • try represents the scenario where the food is served, and you eat it.

  • catch represents the scenario where the food is not served.

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