The purpose of xml?

They have: 5,633 posts

Joined: Jan 1970

So after reading the introduction on w3schools.com about how wonderful xml is. I spent the night learning it. w3schools was good at helping me understand the concept of xml. (This time yesterday I thought it was a stand-alone language that let you define custom structure. No wonder I was confused ) w3S was not good at helping me put it to use. So I attacked msdn and spent 2 hours teaching my self xml in asp.net (how do I keep teaching my self all this stuff? )
So then I'm sitting there looking at the list of methods and attributes. I can’t figure out what is so great about it. This is the way I see it...
If you want it to work effectively you would need to know the exact tags and attributes that you are going to want to read. If you didn’t then you would need 50 or so lines to reformat the information in the file to a more readable format. So why don’t I stick with what I was doing before, putting that kind of information in a text file?
It’s just as easy. "Read element 3" and "Read from char 15 to \n" are the same thing. So I ask you. What is the purpose of creating a new format?

JeevesBond's picture

He has: 3,956 posts

Joined: Jun 2002

Sounds like you need to get back to basics and indeed use a text file, you can't have learnt everything about XML in a couple of hours. Trust me I have a massive, thick book on the subject that I've spent days reading and still don't profess to have a true understanding of the subject.

If you know XML then what does this mean? You should be able to read and understand that document. Laughing out loud

a Padded Cell our articles site!

They have: 5,633 posts

Joined: Jan 1970

I'm not clameing to know everything. And I have no clue what a dtd is. Its just I havent seen anything in my search to suggest xml is any more usefull then a text file.

Megan's picture

She has: 11,421 posts

Joined: Jun 1999

XML has a lot of great applications. RSS is XML. It's a great way of formatting data so it can be read in different systems. In education, for example, we create learning objects. These are stand-alone learning tools, often created in Flash or director or just html & javascript. Universities like to share these things to they don't always have to be creating them themselves (expensive and time consuming process) so there are various groups and repositories where people can go to trade or borrow learning objects. They are working on devising an xml schema for learning objects that would allow them to be plugged into different repositores with descriptive data attached (such as author, learning objectives, technolgoies required etc.). The problem is they can't decide on what the standard should be!

They have: 5,633 posts

Joined: Jan 1970

I noticed it was real easy to write data into an xml file (via asp.net). But I expected something equivalent to a database when retrieving the data. It’s a good idea to make a plain text based standard so I am in the process of converting to the xml format.
Sorry if that doesnt make since... up all night writeing code and its hard to gater my thoughts.

JeevesBond's picture

He has: 3,956 posts

Joined: Jun 2002

Hmmm, XML isn't really like a database, it's also not designed to be a replacement for one either. As you noted bja it's just a flat text file, what makes it more useful than a simple text file is the standard behind it, versatility but still a consistent set of rules.

There are many parsers for it as well, I've not used .NET much so don't know what the interface is like, is it really any better than writing a text file? And does it provide what you need to write/validate Vs. a DTD?

a Padded Cell our articles site!

They have: 5,633 posts

Joined: Jan 1970

JeevesBond wrote:
There are many parsers for it as well, I've not used .NET much so don't know what the interface is like, is it really any better than writing a text file? And does it provide what you need to write/validate Vs. a DTD?

I still have no clue what a DTD is....its really isnt the diffrent from writing to a text file but it does take away the consirn that there is a extra space right before the line break. That messes everything up. I will be doing more research in xml at a later date. Might even take a class, right now though I need to get optimalsource off the ground so I can have some form of income...
I am awake for 16 hours at a time (and still get 10 hours of sleep) just tring to get some form of income that will use my talents. I will worry about the details when I get time. As for now though... I can add more letters to my resume.

timjpriebe's picture

He has: 2,667 posts

Joined: Dec 2004

bja, I believe even datasets in .NET are actually XML.

They have: 5,633 posts

Joined: Jan 1970

After doing a little research on appending xml I found its usefull if you use a ton of data types that I would of never though existed.
XmlDocument
XmlNode
XmlNodeList
XmlElement

Where I was just streaming it like a text file...
XmlTextReader
XmlTextWriter

I think I like it a little better now Smiling

JeevesBond's picture

He has: 3,956 posts

Joined: Jun 2002

Quote: I believe even datasets in .NET are actually XML.

Ah, so .NET truly is run by XML. I guess MS did do a lot of the development behind XML so makes sense. Smiling

a Padded Cell our articles site!

They have: 5,633 posts

Joined: Jan 1970

I have seen "dataset" here and there but the only time I used it. I like it much better now. I even figured out how to skip around and pull specific data. Next step... RSS!
Speaking of which... how does the browser know to put that rss icon in the corner?

Want to join the discussion? Create an account or log in if you already have one. Joining is fast, free and painless! We’ll even whisk you back here when you’ve finished.