Understanding the Value of Async Function with XMLHttpRequest in JavaScript

Discover how to obtain the inner HTML from an HTTP request using an async function in JavaScript. Learn step-by-step implementation techniques and best practices!
---

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Value of Async Function or Value of HTTP Request

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Understanding the Value of Async Function with XMLHttpRequest in JavaScript

Good evening! If you're new to JavaScript and have stumbled upon the need to fetch data from an HTTP request, you're not alone. Many aspiring developers face the initial challenge of correctly handling XMLHttpRequest to retrieve and utilize inner HTML elements. Today, we're going to dive into how to effectively save values from an HTTP request using async functions in JavaScript.

The Problem: Getting the Inner HTML

When trying to access the innerHTML of an element after sending an HTTP request, you may find it challenging to store that value for further use. Here’s a quick recap of what you'd typically encounter:

You create an instance of XMLHttpRequest and make a GET request.

The next logical step is to save this result as a string, so you can manipulate or use it in other parts of your code. But how do you approach this?

The Solution: Using Async Functions and Promises

To tackle this problem, we can introduce JavaScript's async functionality along with Promises. This will allow us to handle asynchronous operations more effectively. Let’s take a closer look at how to implement this.

Step 1: Modify the Function to Return a Promise

First, let's modify your getBasketCode function to return a Promise. This change will help us handle the asynchronous nature of the XMLHttpRequest.

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Calling the Function

You can now retrieve the value using an asynchronous approach. For example:

[[See Video to Reveal this Text or Code Snippet]]

What if You Are Not in an Async Function?

If you're not in an async function context, you can handle the Promise using .then():

[[See Video to Reveal this Text or Code Snippet]]

Considerations and Best Practices

Error Handling: Always consider implementing error handling in your functions. For instance, check the status of the xhr request to avoid misbehavior if the response is not successful.

Code Structure: Keep your code organized by separating HTTP requests from business logic. This will help you maintain and debug your code easier in the future.

Using Modern Fetch API: While XMLHttpRequest is still widely used, consider adopting the Fetch API if you’re working in modern environments, as it offers a more powerful and flexible feature set.

Conclusion

Fetching values from an HTTP request and saving them as strings can be straightforward with JavaScript's async capabilities and Promises. By modifying your approach as demonstrated, you can effectively harness the value of async functions in your JavaScript applications.

Whether you're a beginner or looking to deepen your understanding, practice regularly to overcome the challenges of asynchronous JavaScript programming. Happy coding!