Benchmark: className vs. setAttribute vs. classList v2

HTML Preparation code:

<div id="foo"></div>

Tests:

className
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.className = "bar"; element.className = null; }
setAttribute
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.setAttribute("class", "bar"); element.removeAttribute("class"); }
classList
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.classList.add("bar"); element.classList.remove("bar"); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
className
setAttribute
classList

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

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Let's break down the provided JSON benchmark.

**Benchmark Definition**

The JSON represents a JavaScript microbenchmarking test case, which compares three different approaches to update the `class` attribute of an HTML element: using `className`, `setAttribute`, and `classList`.

**Approaches Compared**

1. **`className`**: This approach uses the `className` property to set and unset the class name.
2. **`setAttribute`**: This approach uses the `setAttribute` method to set and remove the `class` attribute.
3. **`classList`**: This approach uses the `classList` API to add and remove classes.

**Pros and Cons**

* **`className`**:
	+ Pros: Simple and widely supported, as it's a built-in property of HTML elements.
	+ Cons: May not work as expected in older browsers or with certain CSS rules, as it can lead to unexpected class name behavior (e.g., setting multiple classes at once).
* **`setAttribute`**:
	+ Pros: Highly portable and well-supported across browsers, as it's a standard DOM method.
	+ Cons: Can be slower due to the overhead of setting an attribute, especially in older browsers or with large datasets.
* **`classList`**:
	+ Pros: Efficient and modern API, designed for class management, which can lead to better performance and more predictable results.
	+ Cons: May not work in older browsers that don't support the `classList` API.

**Library/Dependency**

None explicitly mentioned in the provided benchmark. However, if we consider the use of JavaScript features and syntax, we might note that this benchmark doesn't rely on any specific library or framework, making it relatively portable across environments.

**Special JS Feature/Syntax**

There are no special JavaScript features or syntax used in this benchmark beyond the standard DOM APIs and modern class management methods. This makes the test case widely applicable and easily reproducible.

**Alternative Approaches**

Other approaches to update the `class` attribute might include:

* Using CSS classes (e.g., `element.classList.add('bar'); element.style.display = 'none';`)
* Employing template literals or string concatenation
* Leveraging modern JavaScript features like `const classList = document.querySelector('#foo').classList;`

However, these alternatives are not included in this benchmark.

**Conclusion**

The provided JSON benchmark tests three common approaches to update the `class` attribute of an HTML element: using `className`, `setAttribute`, and `classList`. The pros and cons of each approach highlight their strengths and weaknesses, which can impact performance, compatibility, and maintainability.

Related benchmarks:

className vs. setAttribute vs. classList v2 (version: 0)

Comparing performance of: className vs setAttribute vs classList

Created: 6 years ago by: Guest

Jump to the latest result

className

setAttribute

classList

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):