Error with oNodes zXPath in chapter 4

chung · January 15th, 2007, 09:37 AM

Hi:

I like this book so far but hit a problem in chapter 4, "Cross-Browser XPath", p108.

In file "NameSpaceBooks.htm":

var oRoot = oXmlDom.documentElement;
var sXPath = "na:book/pub:name";
var oNodes = zXPath.selectNodes(oRoot, sXPath, sNameSpace);
if (oNodes.length > 0) {
alert(oNodes.length + " nodes selected with '" + sXPath + "'");
}

oNodes.length returns 0 for me.
The file NameSpaceBooks.htm shows as a blank page in both FF and IE.
NameSpaceBooks.xml is fine as far as I can tell.

I am using * JavaScript zXml Library * Version 1.0.2

Any advice appreciated.

Chung Wang

joefawcett · January 15th, 2007, 10:33 AM

There is a slight error in the book regarding how to set namespace mappings for zXml which should be fixed for the next print run.
You need something like:

Code:

var namespace1 = "<namespace URI for na here>";
var namespace2 = "<namespace URI for pub here>";
var oNamespaceMapper = {na: namespace1, pub: namespace2};
var oRoot = oXmlDom.documentElement;
var sXPath = "na:book/pub:name";
var oNodes = zXPath.selectNodes(oRoot, sXPath, oNamespaceMapper);
if (oNodes.length > 0)
{
  alert(oNodes.length + " nodes selected with '" + sXPath + "'");
}

You will need to replace the namespace declarations with the real ones.

--

Joe (Microsoft MVP - XML)