ASP.NET is not just the next version of ASP; it is the next era of web
development. ASP.NET allows you to use a full featured programming language
such as C# (pronounced C-Sharp) or VB.NET to build web applications easily.
ASP.NET still renders HTML
Unfortunately, the Internet still has bandwidth limitations and not every
person is running the same web browser.
These issues make it necessary to stick with HTML as our mark-up language
of choice. This means that web pages won't look quite as amazing as a fully
fledged application running under Windows, but with a bit of skill and
creative flair, you can make some rather amazing web applications with
ASP.NET.
ASP.NET processes all code on the server (in a similar way to a normal
application). When the ASP.NET code has been processed, the server returns
the resultant HTML to the client. If the client supports JavaScript, then
the server will use it to make the clients browser experience quicker and
easier. Even with HTML being the limiting factor here, ASP.NET still
manages to bring true OOP (Object Oriented Programming) to the Internet.
OOP on the Internet
Object Oriented Programming makes it possible to build extremely large
applications, while still keeping your code clean and structured. Now with
ASP.NET, we can do the same on the web. Traditional ASP uses HTML and
VBScript (or Jscript) to process and render pages, but because VBScript is
a scripting language, you were forced to write spaghetti code (VBScript was
entwined in the HTML and ended up rather messy in larger applications).
ASP.NET separates code from display, and you can even have pages with no
ASP.NET code in them at all. By adding references in your HTML (called
controls), you can tell ASP.NET that you want a button here, some text
there, and then in your code, you can manipulate what these controls look
like, what they display, how big they are, etc.
Controls can do more than just display information. You can add events to
controls, so that when a visitor clicks on a button, for example, ASP.NET
executes a function of your choice.
Web Services
One great feature of ASP.NET are Web Services. Web services mean that you
can literally have several pieces of your application on different servers
all around the world, and the entire application will work perfectly and
seamlessly. Web services can even work with normal.NET Windows applications.
For example: A lot of people would like to have a stock ticker on their web
site, but not many people want to manually type in all changes to the
prices. If one company (a stock broker) creates a web service and updates
the stock prices periodically, then all of those people wanting the prices
can use this web service to log in, run a function which grabs the current
price for a chosen company, and return it. Web services can be used for so
many things: news, currency exchange, login verification.. the ways in
which they can be used are limited to your imagination!
Great XML Support
ASP.NET makes it simple to use XML for data storage, configuration and
manipulation. The tools which are built into ASP.NET for working with XML
are very easy to use. XML is excellent for storing information that rarely
changes, because you can just cache that information in the computers
memory after it has been initially extracted.
.NET is still in Beta development
Microsoft is still working on the entire.NET framework, however you can
still download the Beta 2 version (which works just fine... I'm yet to come
across any major bugs) from the ASP.NET homepage. The final release of.NET
is scheduled for February 18th, 2002.
Complete Compatibility
One of the most important goals of.NET was to allow developers to write an
ASP.NET application using multiple programming languages. As long as each
ASP.NET page contains only one programming language, you can mix and match
different pages using different languages and they will work together
seamlessly. This means you can now have a team of developers with half
programming in C#, and the other half in VB.NET, with no need to worry
about language incompatibilities, etc.
A cool little side-affect of all this is that all the programming languages
look very similar, and differ only by their language syntax.
Take the following code snippets for example. They both do exactly the same
thing but the first is written in C#, and the second in VB.NET.
The C# version:
void PageLoad(Object S, EventArgs E) { myLabel.Text "Hello world!!";
The VB.NET version:
Sub PageLoad(S As Object, E As EventArgs) myLabel.Text "Hello world!!"
End Sub
If you take either of the code examples shown above and add the following
HTML to them, then they would both run perfectly inside of an ASP.NET page:
"Hello World" example!< itle>