The Test Page
Now let's see this all at work by looking
at the test page, which is included in the source download as default.asp. We will use the JavaScript alert() function to display the XML because if we show it in the browser
the tags will not be visible.
When it loads, the test page will invoke
the init() function. It will create two instances of the XML DOM, one for the XML source
document, and the second for the dynamic XSL file. The last thing it does is apply the XSL to the
source XML, and saves the resulting string in the "processed" variable. This is our translated XML. The full code is shown
here:
<html>
<head>
<link REL="stylesheet" TYPE="text/css"
HREF="list.css">
</head>
<body>
<hr color=red>
<button
onclick='alert(source.xml);'>1. Show incoming.xml</button>
<button onclick='alert(dynstyle.xml);'>2.
Show dynstyle.xsl</button>
<button
onclick='alert(processed);' id=button1 name=button1>
3. Show Translation
</button><br>
<hr color=red>
<script
FOR="window" EVENT="onload">
init();
</script>
<script>
var source;
var sourceName =
"incoming.xml";
var dynstyle;
var dynstyleName =
"interpreter.asp";
var processed =
"";
function init(){
// Do init stuff. Called by the parent frame.
source = new ActiveXObject('Microsoft.XMLDOM');
source.async = false;
source.load(sourceName);
// did the XML file load OK?
if (source.parseError.errorCode != 0){
msg = 'Error loading SOURCE file.'
msg += '\nDescription: ' + source.parseError.reason
msg += '\nSource text: ' + source.parseError.srcText
}
root = source.documentElement;
dynstyle = new ActiveXObject('Microsoft.XMLDOM');
dynstyle.async = false;
dynstyle.load(dynstyleName)
// did the XML file load OK?
if (dynstyle.parseError.errorCode != 0){
msg = 'Error loading DYNSTYLE file.'
msg += '\nDescription: ' + dynstyle.parseError.reason
msg += '\nSource text: ' + dynstyle.parseError.srcText
}
processed = source.transformNode(dynstyle)
}
</script>
</body>
</html>
I have provided three buttons on the test
page that show the three entities that make up this example:
q
Button 1 shows the original
un-translated source document (incoming.xml)
q
Button 2 shows the
dynamically-generated XSL returned as a result from interpreter.asp
q
Button 3 shows the translated version
of the source document, after the style has been applied to it.
How it Works
The following screen shot shows the
un-translated source document:
This screen shot shows our dynamically
generated XSL:
This final screen shot shows the result of
the translation:
Summary
In this chapter, we have seen a way to use
ASP to generate an XSL file dynamically. We did this by using an ASP page to
create an instance of the XML DOM and employing DOM methods to build the result
tree. The information needed to build the result tree came from the contents of
an XML file. A test web page then used the dynamic XSL to translate from one
XML structure to another.
So now we have finished our discussion on
styling XML for our web browsers. We will use XSL frequently as we progress
through this book. In the next chapter we shall move on to storing and
retrieving XML data from databases using ActiveX Data Objects (ADO).
