Benchmark: Updating Classes v1

HTML Preparation code:

<div class="new-page-container"><p id="superID">Hello World</p></div>

Script Preparation code:

document.getElementById("superID").className = "";

Tests:

setAttribute
document.getElementById("superID").setAttribute('class', 'test');
className
document.getElementById("superID").className = "test";
classList-Add
document.getElementById("superID").classList.add("test");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
setAttribute
className
classList-Add

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 6 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36

Browser/OS: Chrome 67 on Windows

View result in a separate tab

Test name	Executions per second
setAttribute	1661495.9 Ops/sec
className	1906266.0 Ops/sec
classList-Add	1499667.5 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Overview**

The current benchmark measures the performance of three different methods to update the class name of an HTML element: `setAttribute`, `className`, and `classList.add`. The test is run on a fixed HTML page with a single element that will be updated.

**Test Case 1: `setAttribute`**

* **Purpose**: Set the 'class' attribute of an element using JavaScript.
* **Library**: None
* **Special JS feature/syntax**: None

In this approach, the `setAttribute` method is used to set the value of the 'class' attribute. This method can be slower than other approaches because it requires parsing and updating the DOM tree.

**Pros:**

1. **Flexibility**: Can be used with any element that supports attributes.
2. **Simple implementation**: The syntax is straightforward, making it easy to implement.

**Cons:**

1. **Slow performance**: Requires parsing and updating the DOM tree.
2. **Less efficient than other methods**: Compared to `className` and `classList.add`, which are more optimized.

**Test Case 2: `className`**

* **Purpose**: Set the class name of an element using JavaScript.
* **Library**: None
* **Special JS feature/syntax**: None

In this approach, the `className` property is used to set the value of the class attribute. This method is optimized for performance because it directly updates the class list.

**Pros:**

1. **Fast performance**: Updates the class list directly.
2. **Efficient implementation**: The syntax is concise and efficient.

**Cons:**

1. **Limited flexibility**: Only works with elements that support class names (most modern browsers).
2. **May not work in older browsers**: Some older browsers may not support this property.

**Test Case 3: `classList.add`**

* **Purpose**: Add a class to an element using JavaScript.
* **Library**: `classList` API (introduced in ECMAScript 2015)
* **Special JS feature/syntax**: `classList` API

In this approach, the `classList.add` method is used to add a class to the element. This method is optimized for performance because it uses the `classList` API, which is designed specifically for managing class names.

**Pros:**

1. **Fast performance**: Updates the class list directly.
2. **Efficient implementation**: The syntax is concise and efficient.
3. **Flexibility**: Works with elements that support class lists (most modern browsers).

**Cons:**

1. **Limited availability**: Only works in browsers that support the `classList` API (introduced in ECMAScript 2015).
2. **May require polyfills**: Older browsers may not support this property.

**Other Alternatives**

* **CSS classes**: Another approach is to update the class list using CSS classes. This can be done by adding or removing class names from the element's style attribute.
* **Using a library**: There are libraries like jQuery, which provides a more convenient way of updating class names and other DOM properties.

In conclusion, the `classList` API (used in Test Case 3) is the most optimized approach for updating class names. However, its availability is limited to modern browsers that support ECMAScript 2015 and later versions. The `className` property (Test Case 2) is a more flexible alternative but may not work in older browsers. The `setAttribute` method (Test Case 1) is slower and less efficient than the other two approaches.

Related benchmarks:

Updating Classes v1 (version: 0)

comparing the 4 Titans

Comparing performance of: setAttribute vs className vs classList-Add

Created: 6 years ago by: Guest

Jump to the latest result

setAttribute

className

classList-Add

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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