javascript

XSLT Support in Browsers
Chapter 15: XML in JavaScript
XSLT is a companion technology to XML that makes use of XPath to transform one document
representation into another. Unlike XML and XPath, XSLT has no formal API associated with it and is
not represented in the formal DOM at all. This left browser vendors to implement support in their own
way. The first browser to add XSLT processing in JavaScript was IE.
XSLT in Internet Explorer
As with the rest of the XML functionality in IE, XSLT support is provided through the use of ActiveX
objects. Beginning with MSXML 3.0 (shipped with IE 6.0), full XSLT 1.0 support is available via
JavaScript.
Simple XSLT Transformations
The simplest way to transform an XML document using an XSLT style sheet is to load each into a DOM
document and then use the transformNode() method. This method exists on every node in a document
and accepts a single argument, which is the document containing an XSLT style sheet. The
transformNode() method returns a string containing the transformation. Here is an example:
//load the XML and XSLT (IE-specific)
xmldom.load(“employees.xml”);
xsltdom.load(“employees.xslt”);
//transform
var result = xmldom.transformNode(xsltdom);
This example loads a DOM document with XML and a DOM document with the XSLT style sheet. Then,
transformNode() is called on the XML document node, passing in the XSLT. The variable result is
then filled with a string resulting from the transformation. Note that the transformation began at the
document node level because that ’ s where transformNode() was called. XSLT transformations can also
take place anywhere in the document by calling transformNode() on the node at which you want the
transformations to begin. Here is an example:
result = xmldom.documentElement.transformNode(xsltdom);
result = xmldom.documentElement.childNodes[1].transformNode(xsltdom);
result = xmldom.getElementsByTagName(“name”)[0].transformNode(xsltdom);
result = xmldom.documentElement.firstChild.lastChild.transformNode(xsltdom);
If you call transformNode() from anywhere other than the document element, you start the
transformation at that spot. The XSLT style sheet, however, still has access to the full XML document
from which that node came.
Complex XSLT Transformations
The transformNode() method gives basic XSLT transformation capabilities, but there are more
complex ways to use the language. To do so, you must use an XSL template and an XSL processor. The
first step is to load the XSLT style sheet into a thread - safe version of an XML document. This is done by
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