XML DOM Model

A DOM document is a collection of nodes or pieces of information, organized in a hierarchy.

XML DOM Structure

Everything in an XML document is a node and even the document itself is a node.

Some types of nodes can have children nodes of various types, and others are leaf nodes that cannot have anything under them in the document structure.

The following table shows the various types of nodes and for each the possible child nodes:

Node	Child nodes
Document	Element (maximum of one), ProcessingInstruction, Comment, DocumentType (maximum of one)
DocumentFragment	Element, ProcessingInstruction, Comment, Text, CDATASection, EntityReference
EntityReference	Element, ProcessingInstruction, Comment, Text, CDATASection, EntityReference
Element	Element, Text, Comment, ProcessingInstruction, CDATASection, EntityReference
Attr	Text, EntityReference
ProcessingInstruction	No children
Comment	No children
Text	No children
CDATASection	No children
Entity	Element, ProcessingInstruction, Comment, Text, CDATASection, EntityReference
Notation	No children

Example

<?xml version = "1.0"?>
<Company>
	<Employee category="technical">
		<FirstName>Tom</FirstName>
		<LastName>Nolan</LastName>
		<ContactNo>1234567890</ContactNo>
	</Employee>
	<Employee category="support">
		<FirstName>Ryan</FirstName>
		<LastName>Reynolds</LastName>
		<ContactNo>1123456789</ContactNo>
	</Employee>
</Company>

note

Learn more about Nodes in XML DOM Nodes chapter.