Benchmark: jQuery class selector

HTML Preparation code:

<div id='curBody1'>
  <div>
    <span>
      <input type='button'/>
    </span>
  </div>
</div>
<div id='curBody2'>
  <div>
    <span>
      <input type='button' class='desired-element'/>
    </span>
  </div>
</div>

Script Preparation code:

var curElement = null;

Tests:

Id and class chaining selector
curElement = $('#curBody2 .desired-element');
Class selector only
curElement = $('.desired-element');
Id selector then .find
curElement = $('#curBody2').find('.desired-element');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Id and class chaining selector
Class selector only
Id selector then .find

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 8 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36

Browser/OS: Chrome 52 on Windows

View result in a separate tab

Test name	Executions per second
Id and class chaining selector	111136.4 Ops/sec
Class selector only	538559.9 Ops/sec
Id selector then .find	399760.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what is being tested in the provided JSON.

**Benchmark Purpose:**

The benchmark measures the performance difference between three different ways of selecting an HTML element using jQuery:

1. Using only the class selector (`$(selector)`)
2. Using the id selector followed by a `.find()` method to navigate to the child element (`$('#selector').find('.desired-element')`)
3. Using both id and class chaining selectors together (`$('#selector .desired-element')`)

**Options Compared:**

The benchmark compares the performance of these three approaches:

1. **Class selector only**: `$(selector)`
2. **Id selector then `.find()`**: `$('#selector').find('.desired-element')`
3. **Id and class chaining**: `$('#selector .desired-element')`

**Pros and Cons of Each Approach:**

*   **Class selector only (1)**:
    *   Pros: Simple, easy to read, and write.
    *   Cons: May not be as efficient if the selector is complex or has many elements with the same class.
*   **Id selector then `.find()` (2)**:
    *   Pros: Can be more efficient than using a class selector if there's only one element with the desired class.
    *   Cons: May require more code and can lead to slower performance if used unnecessarily or in complex scenarios.
*   **Id and class chaining**: `$('#selector .desired-element')`
    *   Pros: Can provide better performance than using an id selector followed by `.find()` when there's only one element with the desired class. It also reduces the number of DOM lookups required.
    *   Cons: Requires that the selector is accurate, and if not, it can lead to incorrect results or slower performance.

**Library and Purpose:**

The benchmark uses jQuery as a library for its utility functions and methods. Specifically, it relies on `$(selector)` and `.find()` to select and navigate elements within the DOM.

**Special JS Feature/Syntax:**

This benchmark does not specifically use any special JavaScript features like ES6 syntax or async/await. However, it assumes that the user has access to jQuery's utility functions and methods.

**Other Alternatives:**

If you want to test similar benchmarks without using jQuery:

*   You can use vanilla JavaScript with DOM traversal APIs (e.g., `document.querySelector()`, `getElementsByClassName()`) or library alternatives like React or Angular.
*   Alternatively, you could write a custom benchmarking script using a language like Python or Node.js that uses a similar approach to measure performance differences.

Keep in mind that each alternative may require adjustments to the benchmark setup and test cases.

Related benchmarks:

jQuery class selector (version: 0)

This will test the difference between selecting an element using its class vs getting a handle on the parent element and then navigating to the child.

Comparing performance of: Id and class chaining selector vs Class selector only vs Id selector then .find

Created: 8 years ago by: Guest

Jump to the latest result

Id and class chaining selector

Class selector only

Id selector then .find

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):