🌳 DOM Manipulation

Master the art of dynamically changing web pages with JavaScript

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DOM Manipulation Curriculum

10
DOM Units
~50
DOM Methods
25+
Interactive Projects
Real-time
Updates
1

Understanding the DOM

Learn what the DOM is and how it represents web page structure.

  • What is the DOM?
  • DOM tree structure
  • Nodes and elements
  • Document object
  • Browser rendering
  • DOM vs HTML
  • Live vs static
  • Developer tools
2

Selecting Elements

Master different methods to find and select DOM elements.

  • getElementById
  • getElementsByClassName
  • getElementsByTagName
  • querySelector
  • querySelectorAll
  • CSS selectors
  • NodeList vs HTMLCollection
  • Selection performance
3

Modifying Content

Change text, HTML content, and attributes of DOM elements.

  • textContent property
  • innerHTML property
  • innerText vs textContent
  • outerHTML property
  • insertAdjacentHTML
  • Security considerations
  • Performance tips
  • Content sanitization
4

Working with Attributes

Get, set, and manage HTML attributes and data attributes.

  • getAttribute method
  • setAttribute method
  • removeAttribute method
  • hasAttribute method
  • Data attributes
  • Boolean attributes
  • Custom attributes
  • Attribute vs property
5

Styling Elements

Dynamically change CSS styles and classes of elements.

  • style property
  • CSS properties
  • className property
  • classList methods
  • add and remove classes
  • toggle classes
  • Computed styles
  • CSS-in-JS patterns
6

Creating and Removing Elements

Dynamically add new elements and remove existing ones from the DOM.

  • createElement method
  • createTextNode method
  • appendChild method
  • insertBefore method
  • removeChild method
  • cloneNode method
  • Document fragments
  • Modern insertion methods
7

DOM Navigation

Navigate between DOM elements using relationship properties.

  • parentNode property
  • childNodes property
  • firstChild and lastChild
  • nextSibling and previousSibling
  • Element-specific navigation
  • parentElement property
  • children property
  • Traversal best practices
8

Event Handling

Handle user interactions and DOM events effectively.

  • addEventListener method
  • Event types
  • Event objects
  • Event propagation
  • preventDefault method
  • stopPropagation method
  • Event delegation
  • Removing event listeners
9

Form Manipulation

Work with forms, inputs, and form validation using JavaScript.

  • Form elements
  • Input values
  • Form validation
  • Submit events
  • FormData API
  • Input events
  • Form serialization
  • Custom validation
10

Advanced DOM Techniques

Master advanced DOM manipulation patterns and performance optimization.

  • Virtual DOM concepts
  • DOM performance
  • Batch operations
  • Intersection Observer
  • Mutation Observer
  • Web Components
  • Shadow DOM
  • Best practices

Unit 1: Understanding the DOM

Learn what the DOM is and how it represents web page structure.

What is the DOM?

Understand the Document Object Model and its role in web development.

Document Object Model Tree Structure
The DOM (Document Object Model) is a programming interface that represents HTML documents as a tree of objects. It allows JavaScript to access and manipulate the content, structure, and styling of web pages dynamically.
Document
└── html
    ├── head
    │   ├── title
    │   └── meta
    └── body
        ├── h1
        ├── p
        └── div
// Accessing the DOM
console.log(document); // The entire document
console.log(document.title); // Page title
console.log(document.body); // Body element
console.log(document.head); // Head element

// Document provides the entry point to DOM

DOM Tree Structure

Learn how HTML elements are organized in a hierarchical tree structure.

DOM Node Types:
• Element nodes: HTML tags like <div>, <p>, <span>
• Text nodes: Actual text content inside elements
• Attribute nodes: Element attributes like class, id
• Comment nodes: HTML comments
• Document node: The root of the entire tree
Node Relationships:
Every node in the DOM tree has relationships with other nodes: parent (the node above), children (nodes below), and siblings (nodes at the same level).

Document Object

Explore the document object and its properties and methods.

Key Document Properties:
• document.documentElement: The <html> element
• document.head: The <head> element
• document.body: The <body> element
• document.title: The page title
• document.URL: The current page URL
// Document object examples
document.title = "New Page Title";
console.log(document.URL);
console.log(document.domain);
console.log(document.readyState);

// Check if document is fully loaded
if (document.readyState === 'complete') {
  console.log('Page fully loaded!');
}

Unit 2: Selecting Elements

Master different methods to find and select DOM elements.

Modern Selection Methods

Use querySelector and querySelectorAll for flexible element selection.

querySelector querySelectorAll CSS Selectors
Modern DOM selection methods use CSS selector syntax, making them powerful and flexible. querySelector returns the first matching element, while querySelectorAll returns all matching elements.
// Modern selection methods
const header = document.querySelector('h1');
const allParagraphs = document.querySelectorAll('p');
const firstButton = document.querySelector('.btn');
const allButtons = document.querySelectorAll('.btn');

// Complex CSS selectors
const navLinks = document.querySelectorAll('nav a');
const firstChild = document.querySelector('ul > li:first-child');
const evenRows = document.querySelectorAll('tr:nth-child(even)');

Legacy Selection Methods

Understand older DOM selection methods that are still widely