1. DOM
Document Object Model

2. The Document Object Model
DOM is language independent
It is platform independent
It is the API for HTML, XHTML and XML
Dom always loads the whole document into a tree (can be a problem with very large documents)

3. 3 Levels of DOM There are three levels of DOM specification
Level 1: manipulation and navigation of HTML and XML documents
Level 2: includes methods for stylesheets and manipulating style objects
Level 3: addresses loading and saving DTDs and Schemas

4. Nodes
Any part of a document—elements, attributes, comments, processing instructions, text—is considered a node
Nodes form a document tree.

5. Sample XML
<?xml version="1.0" encoding="UTF-8" ?> <employees> <employee enum="34567"> <name> <lastname>Smith</lastname> <firstname>Alice</firstname> </name> <status dept="accounting" paytype="salary"/> </employee> </employees>

6. Node Tree lastname Smith name firstname Alice employees employee
Accounting
dept
status
paytype
Salary

7. Node properties attributes Returns all attributes of a node childNodes
Returns all child nodes of a node
firstChild
Returns the first child of a node
lastChild
Returns the last child of a node
nextSibling
Returns the next sibling (nodes that share the same parent are siblings)
nodeName
Returns the node name
nodeType
Returns the node type as a number
nodeValue
Returns the value of a node
parentNode
Returns the parent of a node
previousSibling
Returns previous sibling
ownerDocument
Returns owner document of a node

8. Node Methods appendChild(newchild) Appends a new child node
cloneNode(boolean)
Returns an exact copy of the node. If boolean set to true also copies child nodes
hasChildNodes()
Returns true if there are child nodes
insertBefore(newNode, refNode)
Inserts a new node before the reference node
removeChild(nodeName)
Removes a child node
replaceChild(newNode, oldNode)
Replaces a child node with a new child node

9. Node Types Element Attribute Text CDATA Section Entity Reference
Processing instruction
Comment
Document
Document type
Document fragment
notation