Parsing existing XML
First, I'll show you how easy it is to parse—that is, get the information out of—an existing chunk of XML. Suppose you have a plain text file (Company.xml) that contains some XML.
Company.xml
<?xml version="1.0" encoding="UTF-8"?>
<company name="Macromedia">
<location name="Newton">
<employees>
<person>Demi Moore</person>
<person>Bruce Willis</person>
</employees>
</location>
<location name="San Francisco">
<employees>
<person>Tom Cruise</person>
<person>Ben Forta</person>
<person>Nicole Kidman</person>
</employees>
</location>
</company>
As you can see, this simple XML fragment contains information about a company called Macromedia. Two of its office locations are listed, with some employees from each location. Of course, the structure of this example is a bit simpler than XML you would usually encounter in the wild (elsewhere on the web), but it is sufficient for the purposes of this article.
One of the things about XML—maybe the key thing—is that the information in nearly any XML document can be thought of as forming a "hierarchy," or a "tree." Here, the <company> element is a container for the <location> elements, which are containers for the <person> elements. Try to imagine this hierarchy visually. You might find that it is similar to a Windows Explorer directory structure:
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Now, why am I pounding away at this concept? Hasn't this all been covered—the inherently relational tree-like structure of it all, the parent-child relationship between the various nodes in the tree, and so on—in a thousand other books, websites, and magazine articles? Sure it has. I'm just dwelling on it for the moment in the hopes that you'll think of some existing type of data within ColdFusion's CFML language that also is inherently tree-like. Cue Mr. Burns from "The Simpson's": Hmmm. Some other data type that can hold all sorts of information in a hierarchical manner..where you can refer to the various pieces of information (company, location, person and so forth) by name... yes, a tree-like structure...
Aha! Of course, that familiar face: the ColdFusion structure (fondly called Struct in social circles). Conceptually, it's similar to the underlying logical structure of nearly any XML document. For this reason, when ColdFusion parses an XML document, it returns the information from the document in a form that's very, very similar to a ColdFusion structure. Just use the familiar, dot notation syntax to refer to the various pieces of information in the structure. Then use the familiar structure-related functions (such as StructKeyExists(), StructInsert() and so on) to find out the elements within the XML document, or to make changes to the XML data. Release the hounds!
Parsing your first XML document
Like many things, all this talk of structures and whatnot is easier to understand when you see it in action. Take a look at how you might parse the sample Company.xml file in a ColdFusion page. For simplicity's sake, assume that you've saved the following CFML code as a file named ParseXML.cfm, in the same folder as your Company.xml file. It only takes three lines of code for ColdFusion MX to parse the XML, as follows.
ParseXML.cfm
<!--- 1. We want to work with the Company.xml file, --->
<!--- which is in the same folder as this CF template --->
<CFSET MyXmlFile = ExpandPath("Company.xml")>
<!--- 2. Read XML file into string variable called MyXmlCode --->
<CFFILE
ACTION="READ"
FILE="#MyXmlFile#"
VARIABLE="MyXmlCode">
<!--- 3. Parse the XML into an XML "Object" --->
<!--- (very similar to a CFML Structure) --->
<CFSET MyXml = XmlParse(MyXmlCode)>
That's it. The first two lines of code aren't even new for ColdFusion MX. The first line returns a fully qualified pathname for the Company.xml file (including the c:\, if you're using Windows). The pathname is stored as the variable MyXmlFile, which passes to the cffile tag. The cffile tag reads the contents of the XML file into a string variable named MyXmlCode. Of course, if the XML you wish to parse is on a remote web server somewhere else, you can grab it
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just as easily by substituting the cffile with a cfhttp tag above. You'll see a couple examples of that later.
Now you use a new function called XmlParse(), which accepts any properly formatted XML code as a string, returning a special structure-like item called an XML Document object. This XML Document object (named MyXml in this article) contains all of the information that was contained in the XML code (for this article, this would be the contents of the Company.xml file). So, while this code doesn't produce any output yet, ColdFusion MX has now parsed the XML and is waiting for your next move.
). Would this be too big of a project to undertake and if not where are some places I can know to learn how to do some of the mentioned ideas? 
