Enhancing jQuery DOM Manipulation: Best Practices for Optimal Performance.
Tags: jquery, webdev, productivity
Published: 2023-12-26 05:25:19

Enhancing jQuery DOM Manipulation: Best Practices for Optimal Performance.

DOM (Document Object Model) manipulation is the changing of the properties( shape, size, color, position, text, sound, etc.) of an element in a web document without refreshing the page.
Manipulating the DOM successfully is one of the most important tasks in web development. It enables developers to dynamically change the HTML elements, content, and style of a web page using JavaScript. 

Optimizing DOM manipulation ensures faster load-time, lower server costs, a smoother and better user experience, and improves the performance of your website. There are many methods to optimize the DOM manipulation of a web page. Some different libraries and frameworks specialize in easing the task of manipulating the DOM, but in this article, we will be looking at jQuery.

##jQuery's Role in DOM Manipulation 

jQuery is a lightweight JavaScript library. It allows developers to write shorter codes to accomplish simple tasks that require many lines of native JavaScript code by replacing common JavaScript tasks with simple and easy-to-remember methods that can be called using a few lines of code. Among other libraries, jQuery is a popular choice due to its simplicity and extensive support for DOM manipulation, making it accessible to developers on all levels.

Using native JavaScript to manipulate the DOM would require more time, syntax, lines of code, and thinking power. jQuery makes all that hard work simple by reducing the need for all that syntax, reducing the number of codes for common tasks, and offering cross-browser compatibility, which cancels the need to write different functions for specific browsers.

##The Best Practices For Simplified DOM Manipulation

It has been established that jQuery makes it easier to manipulate the DOM in JavaScript, but there are still strategies and practices to follow to make the operations of your website run even smoother. Below are the best practices to follow to make it even better.

###Minimize DOM Operations
Reducing activities on the DOM to the minimum makes it more efficient, and efficiency is critical to a responsive website. Here is how to minimize operations.

- 
Bundle multiple DOM changes into one method. Too many single changes to the DOM would make your web page slower. Combining style, content, and attribute changes would make a responsive website even smoother.

- 
Utilize selectors such as IDs and classes to target element selection. By using these selectors wisely, you can precisely pick elements without traversing the entire DOM, leading to quicker operations.

###Efficient jQuery Object Caching
Object caching is the storage of references to frequently accessed DOM elements into variables for easy access. Instead of querying the DOM for the same element multiple times, you can store it in a variable using `$.cache` and then use that variable whenever you need to access the element.

Caching your DOM elements drastically improves the speed of your code execution.

###Optimized Selector Usage
jQuery selectors are methods used to directly select HTML elements from the DOM using attributes, values of attributes, names, classes, IDs, types, and so on to identify the specific element that is selected.

**Selectors are categorized into three types**: basic CSS selectors, positional selectors, and custom jQuery selectors.

**Basic CSS selectors**: use standard CSS rules, syntax, and semantics to select HTML elements. Examples are using `.` and `*` to call classes and IDs, respectively.

**Positional selectors**: are methods that use the position of an element in the DOM to select it. Positional selectors also use the relationship of an element with another element in the DOM to select it, like parents, children, and siblings.

**Custom JQuery selectors**: are methods that were created by JQuery to give developers more selector options than just CSS positional selectors. It allows developers to pick elements based on their header, checkbox, image, file, etc.

To find out more about jQuery selectors, check [here](https://dzone.com/refcardz/jquery-selectors#:~:text=There%20are%20three%20categories%20of,find%20elements%20within%20the%20DOM).

##Techniques for Performance Optimization

**Utilizing Event Delegation:** Event delegation is when the event listener of a parent element is shared by the child element. You simply attach an event listener (click, hover, keypress, etc.) to a parent element, and it will be used by the child element instead of attaching the same event listener to multiple elements.
**Syntax**
```
$(selector).delegate(childSelector,event,data,function)
```
To find out more about the jQuery `delegate()` method, check [here](https://learn.jquery.com/events/event-delegation/#:~:text=Event%20delegation%20allows%20us%20to,are%20added%20in%20the%20future.).

**Efficient Handling of DOM Insertions and Removals:**  When adding new elements to the DOM, you should use methods that are optimized for insertions into the DOM, such as `.after()`, `.before()`, `.insertAfter()`, etc, and when removing elements from the DOM, use methods that are also optimized for removals, such as `.detach()`, `.empty()`, `.remove()`, etc, to improve the performance of your website.

Below is a table that highlights methods for insertions 

| Methods | Uses |
| --------------- | ----------------- |
| .append() | Add content to the end of an element. |
| .prepend() | Add content to the beginning of an element. |
|.after() | Add content right after an element. |
| .before() | Add content just before an element. |
 
**Optimal Animation With Minimal DOM Manipulation:** 
jQuery has convenient animation methods, but excessive animations can negatively impact performance. Here are some ways to optimize animations for enhanced performance.

Limit animations by avoiding unnecessary animations, especially indefinite loops. Decide whether an animation is necessary and how it affects the user experience.
Use `animate()` to pile and queue multiple animations into one batch of operations.
Use CSS transitions more frequently. Since they are GPU-accelerated and offloaded to the browser's rendering engine, they are more efficient than jQuery animations.

**Avoiding Overly Nested Method Chaining:** 
Method chaining is simply writing multiple jQuery functions (in the same element) in a single line. 

While method chaining has its merits, having too many jQuery statements in our code can cause performance degradation because it has to continuously re-access the same elements and use the same selectors, which slows down the execution of your code. 

##Summary 
To enhance DOM manipulation and optimize operations on your website, you're going to have to write shorter and cleaner codes. But first, you are going to have to write your code the way you learned how to and ensure it works. Then you can go through your code and ask yourself, “Is this short and clean enough?”. If not, then you can begin editing your code to be shorter and cleaner using the strategies and best practices listed above.

Writing optimized, shorter, and cleaner code would make your code easy to read, more scalable, and easier to maintain. It would also improve the performance of your web page, which would in turn enhance the user experience.