Benchmark: jQuery by class vs Document.getElementsByClassName

HTML Preparation code:

<script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-3.1.0.min.js"></script>
<div id="testElement" class="testClass"></div>
<div id="testElement2" class="testClass"></div>
<div id="testElement3" class="notTestClass"></div>

Tests:

jQuery
var el = $(".testClass")[0]; var className = el.className;
Vanilla JS
var el = document.getElementsByClassName('testClass')[0]; var className = el.className;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
jQuery
Vanilla JS

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.6.1 Safari/605.1.15

Browser/OS: Safari 16 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
jQuery	947265.4 Ops/sec
Vanilla JS	9766132.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Measuring JavaScript performance is crucial for optimizing code and ensuring smooth user experiences.

**Benchmark Definition Explanation**

The provided JSON represents a benchmark comparison between two approaches: using jQuery to get an element by its class name and using the native `document.getElementsByClassName` method in vanilla JavaScript. The goal of this benchmark is to measure which approach is faster.

**Options Compared**

Two options are being compared:

1. **jQuery**: A popular JavaScript library that simplifies DOM manipulation.
2. **Vanilla JS**: The native JavaScript API for interacting with the Document Object Model (DOM).

**Pros and Cons of Each Approach**

* **jQuery:**
	+ Pros:
		- Easier to use, especially for complex DOM queries
		- Provides a simpler syntax for selecting elements by class name
	+ Cons:
		- Adds an additional library dependency, which can increase page load times
		- May introduce additional overhead due to the library's internal workings
* **Vanilla JS:**
	+ Pros:
		- No additional library dependencies, making it lighter and faster
		- Directly uses native DOM methods, reducing overhead
	+ Cons:
		- Requires more complex syntax for selecting elements by class name

**Library Description**

In the provided benchmark, jQuery is used to get an element by its class name. The `$(selector)` method returns a jQuery object containing the selected elements. In this case, `$(".testClass")[0]` selects the first element with the class "testClass" and assigns it to the variable `el`. The subsequent line of code extracts the value of the `className` property from the selected element.

**Special JS Feature or Syntax**

The benchmark uses the **querySelector** method (not shown in the provided JSON), which is a newer feature introduced in ECMAScript 2019. However, since querySelector is not used directly, we'll focus on the methods used instead: `document.getElementsByClassName` and `$`.

**Alternative Approaches**

If you need to get an element by its class name without using jQuery or the native `document.getElementsByClassName` method, you can use other approaches:

* **CSS Selectors**: You can use CSS selectors in JavaScript to select elements. For example: `document.querySelector('.testClass')`
* **querySelectorAll**: Similar to querySelector, but returns all matching elements.
* **Element.prototype.matches**: Introduced in ECMAScript 2017, this method allows you to test an element against a set of selectors.

Keep in mind that these alternatives might have varying degrees of complexity and performance compared to the native `document.getElementsByClassName` method or jQuery's class-based selection.

Related benchmarks:

jQuery by class vs Document.getElementsByClassName (version: 0)

Comparing speed of getting element by id with jQuery vs Vanilla JS

Comparing performance of: jQuery vs Vanilla JS

Created: 8 years ago by: Guest

Jump to the latest result

jQuery

Vanilla JS

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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