How to Efficiently Change/Add to Multiple IDs/Classes in HTML with JavaScript

Discover how to update multiple `ID`s and `classes` in your HTML using JavaScript efficiently. Follow our guide for easy implementation!
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How to Efficiently Change/Add to Multiple IDs/Classes in HTML with JavaScript

As web developers, we often find ourselves needing to dynamically manage multiple elements on a page — especially when dealing with forms. A common question arises: Is there a way to change or add parameters to multiple IDs or classes within HTML using JavaScript? This is particularly useful when you have multiple links that need the same additional parameters appended to their URLs.

In this guide, we’ll walk through how to effectively update all relevant elements without writing repetitive code. Let's dive into a practical solution!

The Problem: Managing Multiple Links

You may have a scenario where multiple links on your webpage need the same parameters added to their href attributes. Here’s a basic example of how you might set up your HTML for these links:

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

You attempt to update the href attributes using the following JavaScript:

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

However, this doesn’t work as intended. The getElementsByClassName method returns a collection of elements, and you cannot assign a value to href like that. But don't worry — there is a better way!

The Solution: Iterating Over Elements with JavaScript

The key to solving this problem lies in iterating over each element that matches the class name and updating its href attribute individually. Here are two effective methods to achieve this:

Method 1: Traditional For Loop

Select the elements by class name.

Iterate through the collection with a for loop.

Append the parameters to each href.

Here’s how this looks in code:

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

Method 2: For...of Loop

Alternatively, you can use a for...of loop, which offers simpler syntax and enhanced readability:

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

Summary

Using JavaScript to dynamically update multiple links on your webpage is straightforward with the right approach. By selecting multiple elements and iterating through them, you can efficiently add parameters without redundancy.

Key Takeaways

Use getElementsByClassName to fetch elements by their class.

Loop through the collection using either a traditional for loop or a for...of loop to apply changes.

This method preserves code cleanliness, making it easier to manage multiple links as your project grows.

Now you can confidently manage multiple IDs and classes with JavaScript in your HTML projects. Happy coding!