XML DOM - Nodes

From http://www.w3schools.com (Copyright Refsnes Data)

# XML DOM Nodes

In the DOM, everything in an XML document is a node.

## DOM Nodes

According to the DOM, everything in an XML document is a node.

The DOM says:

- The entire document is a document node
- Every XML element is an element node
- The text in the XML elements are text nodes
- Every attribute is an attribute node
- Comments are comment nodes

## DOM Example

Look at the following XML file (books.xml):

    <?xml version="1.0" encoding="ISO-8859-1"?>
    <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>

The root node in the XML above is named <bookstore>. All other nodes in the document are contained within <bookstore>.

The root node <bookstore> holds four <book> nodes.

The first <book> node holds four nodes: <title>, <author>, <year>, and <price>, which contains one text node each, "Everyday Italian", "Giada De Laurentiis", "2005", and "30.00".

## Text is Always Stored in Text Nodes

A common error in DOM processing is to expect an element node to 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>, holds a text node with the value "2005".

"2005" is not the value of the <year> element!

From http://www.w3schools.com (Copyright Refsnes Data)