Benchmark: window.getComputedStyle vs. className

HTML Preparation code:

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

Tests:

getComputedStyle
var i = 3000; while (i--) { chekele('foo'); } function chekele(element) { return window.getComputedStyle(document.getElementById(element), null).getPropertyValue("display").indexOf('none') === -1; }
className
var i = 3000; while (i--) { chekele('foo'); } function chekele(element) { return document.getElementById(element).className.indexOf('hide') === -1; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
getComputedStyle
className

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 9 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/138.0.0.0 Safari/537.36

Browser/OS: Chrome 138 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
getComputedStyle	2053.4 Ops/sec
className	21729.2 Ops/sec

Autogenerated LLM Summary (model llama3.1:latest, generated one year ago):

LLMs can make mistakes. Check important info.

Let's dive into the provided JSON data and explain what's being tested.

**Benchmark Definition**

The benchmark is named "window.getComputedStyle vs. className", which suggests that we're comparing two different approaches to check if an element has a certain CSS property applied.

**Test Cases**

We have two test cases:

1. **getComputedStyle**: This test case uses the `window.getComputedStyle` method to get the computed styles of an HTML element and then checks if the "display" property is not set to "none". The code loops 3000 times, calling the `chekele` function with the element ID "foo".
2. **className**: This test case uses the `document.getElementById` method to get a reference to the HTML element with ID "foo", and then checks if the element's `className` property does not contain the string "hide". Again, the code loops 3000 times, calling the `chekele` function.

**Library/Feature Used**

No external libraries or special JavaScript features are used in these test cases. They're basic vanilla JavaScript code.

**Pros and Cons of Each Approach**

1. **getComputedStyle**:
	* Pros: This approach allows you to get the computed styles of an element, which can be useful for checking if a certain CSS property is applied.
	* Cons: It requires calling `window.getComputedStyle`, which might incur some overhead.
2. **className**:
	* Pros: This approach is simple and fast, as it only involves accessing the element's `className` property.
	* Cons: It might not be suitable for checking if a specific CSS property is applied, especially if you need to consider inherited styles.

**Other Considerations**

In this benchmark, we're measuring how many executions per second (EPS) each test case can handle. The results suggest that the **getComputedStyle** approach performs better than the **className** approach on Chrome 129.

**Alternatives**

If you need to check if a specific CSS property is applied, you could consider using other approaches like:

1. Using `document.querySelector` and checking the existence of a specific selector.
2. Accessing the element's `style` object and checking for the presence of a specific style attribute.
3. Using a library like jQuery or a similar utility to simplify your code.

Keep in mind that these alternatives might have their own trade-offs, such as performance overhead or added complexity. The best approach depends on your specific use case and requirements.

Related benchmarks:

window.getComputedStyle vs. className (version: 0)

Comparing performance of: getComputedStyle vs className

Created: 7 years ago by: Guest

Jump to the latest result

getComputedStyle

className

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.1:latest, generated one year ago):