XML Demystified

CHAPTER 10 MSXML
File name:
The first line creates the input field, and the second line creates the button.
Look at the opening tag on the HTML document and you’ll see that you
tell the browser to call the LoadDocument() JavaScript function each time that the
HTML page is loaded into the browser. This causes the browser to load the default
file and display it in the text area of the web page.
Notice that the onclick attribute of the input button also calls the LoadDocument()
function when the button is selected. This time the LoadDocument() function loads
the file that’s named in the File name: input box, which is then displayed in the text
area of the web page replacing the current file. You may want to use this button
periodically to refresh the XML document to its original state.
The LoadDocument() Function
A function is a piece of code that contains one or more lines of code that execute
only if the function is called by another part of the application. Each function has a
unique name that’s used to call it. A function is defined before it’s called. You’ll
notice that the LoadDocument() function is defined at the beginning of the HTML
file.
LoadDocument() is a JavaScript function that loads a document. Here’s what it
looks like:
var objXML;
function LoadDocument()
{
var inputfile = document.all("inputfile").value;
objXML = new ActiveXObject("MSXML2.DOMDocument.4.0");
objXML.async = false;
objXML.load(inputfile);
if (objXML.parseError.errorCode != 0)
{
alert("Error loading input file: " + objXML.parseError.reason);
return;
}
document.all("xmldoc").value = objXML.xml;
}
There are two components shown in this example. The first is objXML. This is
a variable. Think of a variable as a placeholder for a real value. The objXML is a
global variable defined outside the function definition, which means that it can be
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