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Error handling

var oXmlDom = new ActiveXObject(arrSignatures[i]);

return oXmlDom;

} catch (oError) {

//ignore

}

throw new Error(“MSXML is not installed on your system.”);

} else if (document.implementation && document.implementation.createDocument) {

var oXmlDom = document.implementation.createDocument(“”,””,null);

oXmlDom.addEventListener(“load”, function () {

this.__changeReadyState__(4);

}, false);

return oXmlDom;

} else {

throw new Error(“Your browser doesn’t support an XML DOM object.”);

}

Now the Mozilla XML DOM properly supports the

readyState

property (for values of

, and

), the

onreadystatechange

event handler, the

loadXML()

method, and the

xml

property. The following

example works in both IE and Mozilla:

var oXmlDom = new XmlDom();

oXmlDom.onreadystatechange = function () {

if (oXmlDom.readyState == 4) {

alert(oXmlDom.xml);

}

};

oXmlDom.load(“test.xml”);

The main difference between the two is how the two XML DOMs handle errors. But this can be remedied.

Error handling

The last step is to create a

parseError

object for Mozilla. Once again, it’s not possible to provide every

IE property, but you have enough information in the Mozilla parser error XML to mimic most of them.

To begin, this object must be created in the

XmlDom

constructor with all its initial values set:

function XmlDom() {

if (window.ActiveXObject) {

var arrSignatures = [“MSXML2.DOMDocument.5.0”, “MSXML2.DOMDocument.4.0”,

“MSXML2.DOMDocument.3.0”, “MSXML2.DOMDocument”,

“Microsoft.XmlDom”];

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XML in JavaScript

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