data exchange

[Guest_imported]

hello everybody,

i'm feeling a bit frustated.
xml is presented as the ultimate tool for data exchange.
but at the same time all the online tutorials don't
include any kind of example to show the effectivness of that
to beginners.

've been reading lot of tutorial, but nowhere it's mentionned how i can access data on a certain web page,
extract them, manipulate and dispaly them again.

could anyone help?

thanks

 

[chiph]

It's not designed to extract info from an ordinary web page. It's used for program-to-program communications.

So if Program "A" were to write a web page containing a string representation of an XML document, Program "B" could in theory pick it up and read it.

One of the things we use it for is sending data back from a web page after a user has filled out a form. Rather than encoding everything on the URL (which is ugly, and lets people spoof your back-end systems), or encoding the form into the request and using a POST, we put the contents of the form into an XML document and pass that on to a COM+ DLL. The COM+ module takes this parameter and can manipulate it much easier than if it had been a gazillion properties. Faster, too! Another benefit is if we change the parameters that get sent back and forth, we don't break binary COM compatability on the VB DLL, since the parameter signature didn't change.

So, think of XML as a convenient place to store data, and that's all. Later on you can get into stylesheet transformations (which I have yet to learn myself), where you can format one piece of XML as an HTML document for the web, and reformat it as a WAP document for a cellphone, all in one call.

Chip H.

 

[RogerFGay]

All sounds quite interesting. I've been exercising with JavaScript and XML for a few weeks now, all based on on-line tutorials and references (just like jesse apparently). I've gotten somewhere with many things, but the day is coming when I really have to do more to save created data and lots of passing data between programs. (That's one of the fundamental requirements of the kind of programs I intend to build.)

I can see the convenience of the SOAP structure for what I want to do. What I end up doing so far, is to create a SOAP structure in one script, that another script reads, parses and uses and I end up wondering why I bothered wrapping the info in a SOAP structure in the first place. My only answer being that SOAP is a standard so all the programmers who will write programs that my programs will communcate with should be quite sympathetic. And yes, I put the other data in XML form too, so it's easy to stuff it in an XML SOAP message anyway.

The kicker is that a lot of people like XML and XML parsing support is available generally so all these programers don't have to write thousands of parsers to get to data in thousands of different data configurations in files. I was considering the same kind of application that I'd like to build now back in the mid-1980s, and without a standard like XML with groups agreeing on application specific XML standards, the whole thing was a good idea but would have been really really difficult in real life.

Still, like I say, I'm still relatively new at this stuff. I still haven't figured out a good way to write files (haven't done much ASP yet either). I don't yet know if there's a write function associated with the XMLDOM object (I started out with Microsoft.XMLDOM introduced in on-line tutorials). I tried ActiveXObject("Scripting.FileSystemObject&quot hoping it would give me a good general purpose way of reading and writing files from script, but you know it's unsafe, so IE throws up scary warning messages.