javascript

Chapter 15: XML in JavaScript
(continued)
var input = event.input;
alert(xmldom.documentElement.tagName); //”root”
alert(xmldom.documentElement.firstChild.tagName); //”child”
var anotherChild = xmldom.createElement(“child”);
xmldom.documentElement.appendChild(anotherChild);
var children = xmldom.getElementsByTagName(“child”);
alert(children.length); //2
}, false);
//begin parsing
parser.parse(input);
If a parsing error occurs during an asynchronous parse operation, the load event never fires. To catch
those errors, you need to define an error handler using a special interface on the LSParser object called
domConfig .
A change in Opera 9.5 causes the load event to never fire, regardless of the validity
of the XML being parsed. It is unclear if this was intentional or is a bug.
The domConfig property is an instance of the DOMConfiguration type, which was introduced in DOM
Level 3 to indicate the parsing and formatting rules for a specific document. The LSParser also uses this
object to specify additional configuration information. You can set such information using the
setParameter() method. One of the parameters is “ error - handler ” , which is a function that handles
parsing errors. As you can see in the following example, this function receives an exception object as an
argument, allowing you to handle the parsing error appropriately:
var implementation = document.implementation;
var parser = implementation.createLSParser(implementation.MODE_ASYNCHRONOUS, null);
var input = implementation.createLSInput();
input.stringData = “ < root > < child/ > < /root > ”;
//subscribe to load event
parser.addEventListener(“load”, function(event){
var xmldom = event.newDocument;
var input = event.input;
alert(xmldom.documentElement.tagName); //”root”
alert(xmldom.documentElement.firstChild.tagName); //”child”
var anotherChild = xmldom.createElement(“child”);
xmldom.documentElement.appendChild(anotherChild);
var children = xmldom.getElementsByTagName(“child”);
alert(children.length); //2
}, false);
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