DOM Element – Represent and Manipulate XML/HTML Tags

Introduction – Why Learn About DOM Element?

In the DOM (Document Object Model), the Element interface represents an HTML or XML tag—like <div>, <title>, or <book>. It’s the most common node type (nodeType = 1) and is central to reading, modifying, and building structured documents. Mastering Element nodes is essential for manipulating both web content and XML data structures.

In this guide, you’ll learn:

• What the Element node is and how it differs from generic nodes
• How to read and write attributes and content
• Key properties and methods of Element
• Use cases in both HTML and XML contexts

What Is a DOM Element?

A DOM Element is a node that represents a tag in the XML or HTML document. It contains:

• A tagName (e.g., "book", "div")
• Attributes (e.g., id, class)
• Child nodes (text, elements, comments)

All DOM Element objects inherit from the base Node interface.

Example – XML Element

<book id="b101">
  <title>Learn XML</title>
</book>

Here:

• <book> and <title> are both Element nodes
• "Learn XML" is a Text node
• id="b101" is an Attribute node attached to the book element

Key Properties of Element

Key Methods of Element

Example – JavaScript DOM Element Usage

const title = document.createElement("title");
title.textContent = "XML Guide";

const book = document.createElement("book");
book.setAttribute("id", "b101");
book.appendChild(title);

console.log(book.outerHTML);
// <book id="b101"><title>XML Guide</title></book>

Element vs Node vs Attribute

Best Practices for DOM Element

• ✔️ Use createElement() to build new DOM structures
• ✔️ Use getAttribute() / setAttribute() for dynamic attributes
• ✔️ Prefer textContent over innerHTML for safe text insertion
• ✔️ Always check for null when using querySelector() or getElementById()
• Don’t trust innerHTML if security is a concern (XSS risk)
• Avoid modifying DOM until the document is fully loaded

Summary – Recap & Next Steps

DOM Element nodes are the primary components of structured XML/HTML documents. They represent tags, hold attributes, and organize child nodes, making them fundamental to any DOM-based manipulation.

Key Takeaways:

• Elements are nodes representing XML or HTML tags (nodeType = 1)
• Access and modify elements using tagName, attributes, and child nodes
• Use createElement(), setAttribute(), and appendChild() for dynamic content

Real-world relevance: DOM elements power HTML rendering, dynamic JavaScript apps, and XML document creation/manipulation.

FAQs – DOM Element

Is every tag an element?
Yes. Tags like <book>, <div>, <title> are Element nodes.

What’s the difference between innerHTML and textContent?
innerHTML includes tags and markup; textContent is plain text only.

Can I clone an element?
Yes. Use element.cloneNode(true) to copy it with children.

What’s the best way to read all attributes?
Use element.attributes (returns a NamedNodeMap).

How can I create a new element?
Use document.createElement("tagName").