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XML DOM support in Mozilla

+ oError.errorCode + “\n”

+ “Line: “ + oError.line + “\n”

+ “Line Pos: “ + oError.linepos + “\n”

+ “Reason: “ + oError.reason);

}

Another option is to throw your own errors:

if (oXmlDom.parseError != 0) {

var oError = oXmlDom.parseError;

throw new Error(oError.reason + “ (at line “ + oError.line

+ “, position “ + oError.linepos + “)”);

}

Regardless of how you end up representing errors, it’s always best to check the XML DOM for errors

immediately after it’s loaded.

XML DOM support in Mozilla

As with many other things, Mozilla supports a more standard version of the XML DOM than Internet

Explorer. The XML DOM in Mozilla is actually part of its JavaScript implementation, meaning that it

not only evolves with the browser, but it is also readily available on all platforms that Mozilla supports.

Unlike Internet Explorer, which has no XML DOM support on the Macintosh or Unix, Mozilla’s support

crosses all platform boundaries. Additionally, Mozilla’s XML DOM implementation supports DOM

Level 2 functionality, unlike Microsoft’s, which supports only DOM Level 1.

DOM creation

The DOM standard specifies that a method called

createDocument()

be available as part of the

docu-

ment.implementation

object. Mozilla follows this specification exactly, enabling you to create an XML

DOM like this:

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

The three arguments for

createDocument()

are the namespace URL for the document, the tag name for

the document element, and a document type object (always

null

, because no support exists for the doc-

ument type object in Mozilla). The previous line of code creates an empty XML DOM. To create an XML

DOM with a document element, just specify the tag name as the second argument:

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

The MSXML ActiveX controls are available only on Windows; therefore, Internet

Explorer on the Macintosh cannot make use of this functionality. Windows XP

Service Pack 2 introduces new security restrictions on many ActiveX controls, but

MSXML is not one of them (all controls in MSXML are considered to be secure).

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