JavaScript Tutorial
JavaScript DOM Introduction
The DOM (Document Object Model) is a programming interface provided by browsers that allows JavaScript to access and manipulate HTML and XML documents. It represents the structure of a web page as a tree of objects, where each node corresponds to an HTML element, attribute, or text content.
What is DOM?
The DOM is essentially a bridge between HTML content and JavaScript code. It allows developers to dynamically update the content, structure, and style of a web page without needing to reload it.
Think of it as a living representation of your webpage that JavaScript can interact with.
Key Features of the DOM
- Dynamic Manipulation – You can change content, add or remove elements, and update styles dynamically.
- Event Handling – JavaScript can respond to user actions like clicks, hovers, and form submissions.
- Hierarchy Representation – The DOM represents HTML elements in a hierarchical tree structure, making it easier to access and manipulate specific elements.
DOM Tree Structure
Document
└── html
├── head
└── body
├── header
├── main
└── footer- Each HTML element is represented as a node.
- Nodes can have child nodes and parent nodes.
- The root node is always the document object.
Why Learn DOM in JavaScript?
- Create interactive and dynamic websites.
- Handle user events like clicks and form inputs.
- Build web applications that respond instantly without page reloads.
- Work with frameworks like React, Angular, or Vue, which are built on the principles of the DOM.
Core DOM Objects
- document – Represents the entire HTML document.
- element – Represents an HTML tag (like <div> or <p>).
- text – Represents the text content inside an element.
- attribute – Represents the attributes of an element (like id, class, or src).
Example: Accessing an Element
// Access an element by its ID
const heading = document.getElementById("main-heading");
console.log(heading.textContent);
Example: Changing Content
const paragraph = document.querySelector(".intro");
paragraph.textContent = "Welcome to Learn2Kode!";
Summary
The DOM is the backbone of interactive web pages. Understanding it is essential for any JavaScript developer, whether you are working with vanilla JS or modern frameworks.