Benchmark: window.getComputedStyle vs. className2

HTML Preparation code:

<div class="foo"></div>

Tests:

getComputedStyle
var i = 3000; var div = document.getElementsByClassName('foo')[0]; while (i--) { chekele(div); } function chekele(element) { return window.getComputedStyle(element, null).display.indexOf('none') === -1; }
className
var i = 3000; while (i--) { chekele('foo'); } function chekele(element) { return document.getElementsByClassName(element)[0].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:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested.

**Benchmark Overview**

MeasureThat.net is testing two different approaches to check if an element has a style attribute set to "none". The test cases are:

1. `getComputedStyle`: Uses the `window.getComputedStyle` method to get the computed style of an element.
2. `className2`: Uses a custom approach by checking the `className` property of the element.

**Test Case 1: `getComputedStyle`**

In this test case, the script preparation code is:
```javascript
var i = 3000;
var div = document.getElementsByClassName('foo')[0];
while (i--) {
    chekele(div);
}
```
The `chekele` function checks if the element's display style is not "none" using `window.getComputedStyle(element, null).display.indexOf('none') === -1`.

**Pros and Cons**

* **Pros**: This approach is simple and straightforward. It directly checks the computed style of the element.
* **Cons**: This approach can be slower because it involves calling a method that makes an additional HTTP request to retrieve the CSS styles from the server.

**Test Case 2: `className2`**

In this test case, the script preparation code is:
```javascript
var i = 3000;
while (i--) {
    chekele('foo');
}

function chekele(element) {
    return document.getElementsByClassName(element)[0].className.indexOf('hide') === -1;
}
```
This approach uses a custom function `chekele` to check if the element's class name includes "hide". This is done by getting the first child element with the given class name using `document.getElementsByClassName(element)`.

**Pros and Cons**

* **Pros**: This approach can be faster because it doesn't involve making an additional HTTP request to retrieve CSS styles.
* **Cons**: This approach relies on the fact that the class names are already present in the HTML code, which might not always be the case.

**Library and Special JS Feature**

In both test cases, a library (not explicitly mentioned) is used to get elements from the DOM. The `document.getElementsByClassName` method is used to retrieve elements with a specific class name.

There's no special JavaScript feature or syntax being tested in this benchmark.

**Other Alternatives**

If you want to measure performance of getting CSS styles using other approaches, you could consider:

1. Using `getComputedStyle` with a different element (e.g., the root element) to avoid any overhead.
2. Comparing the execution time of `window.getComputedStyle` with the execution time of `className2` in reverse order (i.e., checking if an element is not "hide" instead of checking if it's "none").
3. Using other methods to check if an element has a specific style, such as using ` CSS` APIs like `CSSStyle` or `Web APIs`.
4. Adding more complex cases to the benchmark, such as checking multiple styles or using different class names.

Keep in mind that these alternatives might require additional modifications to the script preparation code and the test cases.

Related benchmarks:

window.getComputedStyle vs. className2 (version: 1)

Comparing performance of: getComputedStyle vs className

Created: 4 years ago by: Registered User

Jump to the latest result

getComputedStyle

className

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):