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The XML Document Object Model (DOM) is a programming interface
for XML documents. It defines the way an XML document can be
accessed and manipulated.
Introduction
As a W3C specification,
the objective for the XML DOM has been to provide a standard
programming interface to a wide variety of applications. The XML
DOM is designed to be used with any programming language and any
operating system.
With the XML DOM, a programmer can create an XML document,
navigate its structure, and add, modify, or delete its elements.
The Node Interface
As you will see in the next section, a program called an XML
parser can be used to load an XML document into the memory
of your computer. When the document is loaded, its information
can be retrieved and manipulated by accessing the DOM.
The DOM represents a tree view of the XML document. The
documentElement is the top-level of the tree. This
element has one or many childNodes that represent the
branches of the tree.
A Node Interface Model is used to access the individual
elements in the node tree. As an example, the childNodes
property of the documentElement can be accessed with a for/each
construct to enumerate each individual node.
The Microsoft XML parser supports all the necessary
functions to traverse the node tree, access the nodes and their
attribute values, insert and delete nodes, and convert the node
tree back to XML.
(Believe it or not: The
official DOM does not include standard functions for loading XML
documents !!)
The following table lists the most commonly used node types
supported by the Microsoft XML parser:
Node Type Example
Document type <!DOCTYPE food SYSTEM "food.dtd">
Processing instruction <?xml version="1.0"?>
Element <drink type="beer">Carlsberg</drink>
Attribute type="beer"
Text Carlsberg
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