Скачать или смотреть Enhance Your JavaScript with a One-Liner Solution for querySelectorAll

Discover a simple way to optimize your JavaScript code by reducing multiple querySelectorAll calls into a single effective line.
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This video is based on the question https://stackoverflow.com/q/64282976/ asked by the user 'klewis' ( https://stackoverflow.com/u/957186/ ) and on the answer https://stackoverflow.com/a/64283047/ provided by the user 'Ruben Helsloot' ( https://stackoverflow.com/u/5015356/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

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Optimizing querySelectorAll for Multiple Instances in JavaScript

When working with the Document Object Model (DOM) in JavaScript, you might find yourself needing to manipulate multiple elements that share the same class or tag. This often leads to repetitive code, especially when using querySelectorAll(). If you've ever written multiple lines to achieve a similar effect, you know how cumbersome it can be. Let's explore how to streamline your code effectively!

The Problem

Consider the following scenario: you have several ul elements in your HTML that all carry the class .shadow-box. You want to remove this class from each of these elements. Traditionally, you might write code like this:

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

While this works, it leads to redundancy in your code with multiple calls to querySelectorAll() and isn't very efficient. So, how can we condense this into a cleaner, more manageable format?

The Solution: Using forEach

The key to reducing your code into a single line is to leverage the forEach() method. This method allows you to loop through each element returned by querySelectorAll() and perform the desired action in a concise manner. Here’s how you can do it:

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

Breaking Down the Solution

querySelectorAll: We still perform one call to querySelectorAll() which returns a NodeList of all elements matching the selector 'main .testimonials ul.shadow-box'.

forEach() Method: Instead of referencing each element by index, we use the forEach() method to iterate through this list.

Removing the Class: For each element (el) in our NodeList, we execute el.classList.remove('shadow-box').

Example HTML and CSS

To better visualize how this works, here’s a sample HTML structure and corresponding CSS we might be dealing with:

HTML

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CSS

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

Conclusion

By utilizing the forEach() method along with querySelectorAll(), you can significantly clean up your JavaScript code and make it more efficient. This not only enhances readability but also keeps your codebase neat and organized.

So, the next time you find yourself repeating the same statement for multiple DOM elements, remember that there’s always a way to optimize! Happy coding!