XML DOM Node
In the DOM, every component in an XML document is a node.
DOM Nodes
According to the DOM, every component in an XML document is a node.
The DOM specifies:
- The entire document is a document node
- Each XML element is an element node
- The text contained in an XML element is a text node
- Every XML attribute is an attribute node
- Comments are comment nodes
DOM Example
Consider the following XML file (books.xml):
books.xml File Code:
<?xml version="1.0" encoding="UTF-8"?>
<bookstore>
<book category="cooking">
<title lang="en">Everyday Italian</title>
<author>Giada De Laurentiis</author>
<year>2005</year>
<price>30.00</price>
</book>
<book category="children">
<title lang="en">Harry Potter</title>
<author>J K. Rowling</author>
<year>2005</year>
<price>29.99</price>
</book>
<book category="web">
<title lang="en">XQuery Kick Start</title>
<author>James McGovern</author>
<author>Per Bothner</author>
<author>Kurt Cagle</author>
<author>James Linn</author>
<author>Vaidyanathan Nagarajan</author>
<year>2003</year>
<price>49.99</price>
</book>
<book category="web" cover="paperback">
<title lang="en">Learning XML</title>
<author>Erik T. Ray</author>
<year>2003</year>
<price>39.95</price>
</book>
</bookstore>
In the XML above, the root node is <bookstore>
. All other nodes in the document are contained within <bookstore>
.
The root node <bookstore>
has four <book>
nodes.
The first <book>
node has four nodes: <title>
, <author>
, <year>
, and <price>
, each of which contains a text node: "Everyday Italian", "Giada De Laurentiis", "2005", and "30.00".
Text is Always Stored in Text Nodes
A common mistake in DOM processing is to assume that element nodes contain text.
However, the text of an element node is stored in a text node.
In this example: <year>2005</year>
, the element node <year>
has a text node with the value "2005".
"2005" is not the value of the <year>
element!