javascript

Chapter 15: XML in JavaScript
These methods aren ’ t used often and are provided mostly for convenience.
Resetting the Processor
Each XSLTProcessor instance can be reused multiple times for multiple transformations with different
XSLT style sheets. The reset() method removes all parameters and style sheets from the processor,
allowing you to once again call importStylesheet() to load a different XSLT style sheet as in this example:
var processor = new XSLTProcessor()
processor.importStylesheet(xsltdom);
//do some transformations
processor.reset();
processor.importStylesheet(xsltdom2);
//do more transformations
Reusing a single XSLTProcessor saves memory when using multiple style sheets to perform
transformations.
Cross - Browser XSLT
The IE-to-XSLT transformation is quite different from the XSLTProcessor approach, so recreating all of
the functionality available in each is not realistic. The easiest cross - browser technique for XSLT
transformations is to return a string result. For IE, this means simply calling transformNode() on the
context node, whereas other browsers need to serialize the result of a transformToDocument()
operation. The following function can be used in IE, Firefox, Chrome, Safari, and Opera:
function transform(context, xslt){
if (typeof XSLTProcessor != “undefined”){
var processor = new XSLTProcessor();
processor.importStylesheet(xslt);
var result = processor.transformToDocument(context);
return (new XMLSerializer()).serializeToString(result);
}
} else if (typeof context.transformNode != “undefined”) {
return context.transformNode(xslt);
} else {
throw new Error(“No XSLT processor available.”);
}
The transform() function accepts two arguments: the context node on which to perform the
transformation and the XSLT document object. First, the code checks to see if the XSLTProcessor type is
defined and if so, it uses that to process the transformation. The transformToDocument() method is
called and the result is serialized into a string to be returned. If the context node has a transformNode()
method, then that is used to return the result. As with the other cross - browser functions in this chapter,
transform() throws an error if there is no XSLT processor available. This function is used as follows:
var result = transform(xmldom, xsltdom);
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