How to Load a Script Dynamically Based on Hostname in JavaScript

Learn how to dynamically load JavaScript files based on whether your website is accessed via `localhost`. This guide provides a straightforward solution to switch scripts depending on the environment.
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Dynamically Loading Scripts in JavaScript Based on URL

If you're a developer dealing with both local and production environments, you might encounter situations where you need to load different scripts depending on your current environment. Specifically, you may want to load a particular JavaScript file when your application is running on localhost versus when it is accessed by a public URL. In this post, we will explore how to achieve that using JavaScript.

The Problem

You want your application to behave differently depending on where it is hosted. For instance, you might have a local script that contains debugging tools or functions that are only relevant during development. When your application is running on a live server, you would want to load a different script that is optimized for production.

The Solution

The key to solving this problem lies in checking the hostname of the current URL and loading the appropriate script based on this check. Let me walk you through a simple JavaScript solution.

Implementation Steps

Here’s how you can dynamically load scripts based on whether your website is being accessed from localhost or not:

Create a New Script Element: We'll first create a new <script> element using JavaScript.

Assign the Script Source: Depending on the result of the hostname check, assign the appropriate source URL for the script.

Append the Script to the Body: Finally, add the script to the document’s body to ensure it gets executed.

Sample Code

Below is a simple example of how to implement this:

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

Explanation of the Code

Checking the Hostname:

Loading the Appropriate Script:

The code assigns the appropriate script URL based on the environment.

Conclusion

Loading different scripts based on the environment is a straightforward task in JavaScript that can enhance your development process. By using the hostname to dynamically include the appropriate JavaScript file, you can create a more efficient workflow that separates your local and production setups.

Now you have a solid method to ensure the right scripts load in the right environment. Happy coding!