Benchmark: getAttribute/setAttribute versus classList

HTML Preparation code:

<div class='testName'>TEST HERE</div>

Tests:

setAttribute/getAttribute
const el = document.querySelector('div') el.setAttribute('name', el.getAttribute('class') + ' testClass2')
classList
const el = document.querySelector('div') el.classList.add('testClass2')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
setAttribute/getAttribute
classList

Fastest: N/A

Slowest: N/A

Autogenerated LLM Sumamry (model llama3.2:3b, generated 3 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested, compared, and the pros and cons of each approach.

**Benchmark Overview**

The measurement is comparing two approaches to set a class on an HTML element in JavaScript:

1. Using the `setAttribute` method to directly set the class attribute.
2. Using the `classList.add()` method to add a class to the element's class list.

**What's being tested?**

* The performance difference between these two approaches on different browsers and platforms (desktop, Ubuntu).

**Options compared:**

1. **`setAttribute`**: Sets the value of an attribute directly.
2. **`classList.add()`**: Adds a class to the element's class list.

**Pros and Cons of each approach:**

### `setAttribute`

Pros:

* Simple and straightforward syntax
* Well-documented and widely supported

Cons:

* Can be slower due to the overhead of setting attributes programmatically
* May not be optimized for modern browsers, which often use more efficient methods

### `classList.add()`

Pros:

* Efficient and fast, as it leverages the browser's internal class management
* Modern browsers often optimize this method for performance

Cons:

* Requires a DOM element to work with (e.g., using `document.querySelector`)
* May not be supported in older browsers or environments where `classList` is not available

**Library used:**

In this benchmark, there is no explicit library mentioned. However, the use of `document.querySelector()` and `classList.add()` implies that these methods are part of the DOM API, which is a standard feature of modern web browsers.

**Special JavaScript features or syntax:**

None mentioned in this specific benchmark. The code uses standard JavaScript syntax for setting attributes and adding classes.

**Other alternatives:**

If you needed to set a class on an element without using `setAttribute` or `classList.add()`, other alternatives might include:

* Using the `style` attribute directly (e.g., `el.style.class = 'newClass'`)
* Setting the `className` property of the element's style object (e.g., `el.style.className = 'newClass'`)
* Using a library like jQuery or another DOM manipulation library that provides similar methods

Keep in mind that these alternatives might have different performance characteristics and may not be as efficient as using `classList.add()`.

In summary, this benchmark measures the performance difference between two common ways to set classes on HTML elements in JavaScript. While `setAttribute` is simple and widely supported, `classList.add()` is often faster due to its optimized nature and reliance on modern browser features.

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:73.0) Gecko/20100101 Firefox/73.0

Browser/OS: Firefox 73 on Ubuntu

View result in a separate tab

Test name	Executions per second
setAttribute/getAttribute	980110.6 Ops/sec
classList	751645.0 Ops/sec

Related benchmarks:

getAttribute/setAttribute versus classList (version: 0)

Comparing performance of: setAttribute/getAttribute vs classList

Created: 4 years ago by: Guest

Jump to the latest result

setAttribute/getAttribute

classList

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Sumamry (model llama3.2:3b, generated 3 days ago):