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Introduction
For any webmaster, once you have created a page with graphics and content, the
next logical step is to make it interactive. You can, of course, go to one of
the remotely hosted scripting sites who will provide you with a simple piece of
code to put on your site, but there is a lot more flexibility if you can create
and install your own scripts which will do exactly what you want.
It's thought by many that this 'server-side scripting' (it is processed by the
server and not the browser, so unlike JavaScript the use of ASP doesn't depend
on someone's browser supporting it) is very difficult to learn, and this has
come from the early languages like Perl, which are difficult to write and even
more difficult to debug. Over the past few years two new languages have emerged,
PHP and ASP. These are easy enough for even the novice webmaser to learn.
What Is ASP?
ASP stands for Active Server Pages. It is basically a server-side scripting
language designed for the Windows Platform, although it is available on
Unix/Linux systems through new systems, although PHP is the more popular choice
for this platform. Active Server Pages is based around VBScript, a variant of
Visual Basic, which makes it very easy to use as the majority of the commands
are plain English and simple to decipher.
As mentioned earlier, ASP is a server-side scripting language. Basically what
this means is that if an ASP page is requested, the web server will process it
and run all the ASP code, before sending the output to the browser. This has two
major advantages over client-side (processed by the browser) scripts like
JavaScript. The first is that there are no compatibility problems. It doesn't
matter if the user is using the latest browser or the oldest, they will see the
same output. The second is that your code is hidden. Because code is executed on
the server, users only ever see the output, so it is safe to put passwords etc.
in your ASP code.
What Do I Need?
ASP is a server-side language, so you will need to make sure that your web
server has the correct software for running it. The most common setup for
running ASP scripts is on a Windows-based server running IIS (Internet
Information Server). It is possible to use Linux-based systems, though, but they
must have the Chillisoft ASP package installed. Most web hosts will publish
whether they support ASP, but if in doubt contact your systems administrator. If
you need a free web host supporting ASP, try visiting Free-Webhosting.info.
Once you have the server ready to accept scripts, running one is as easy as
simply uploading and running the file. You don't need to put it in any
particular place on the server or change any settings. Just upload and run.
ASP Code
When writing ASP you don't need to worry about changing all your HTML, you
simply add ASP code into your HTML pages where needed. YOu also don't need any
special software on your computer, a simple text editor will do. To begin an ASP
page you will first need to tell it what language you have written it in. The
most common (and the one used in this tutorial) is VBScript. You should begin
your page with:
<%@ Language=VBScript %>
All this code does is tell the ASP system that you are writing your page in
VBScript. You will notice that the ASP code is enclosed in special tags. All ASP
code should be enclosed in the 'percent sign tags' in the form:
<% ASP Code Here %>
Code can be written over multiple lines, but any code not enclosed in the ASP
tags will simply be treated as HTML. Similarly and HTML inside these tags but
not specifically sent as output by the code will cause an error.
Testing ASP
Before you start writing scripts it is a good idea to test whether ASP will run
correctly on your server. Make a simple page with the following:
<html>
<head><title>Test Page</title></head>
<body>
This is some HTML. Below this I have ASP<br>
<%@ Language=VBScript %><br>
Nothing should appear above here.
</body>
</html>
and save it as test.asp. Then upload this to your server and access it with your
browser. If it has worked correctly, the page should display and you should only
see the lines:
This is some HTML. Below this I have ASP
Nothing should appear above here.
If the ASP appears in the page or the source of the page, something has gone
wrong. Check the code and also the settings on your server. No ASP should appear
as it should have been processed by the server before it was sent to the
browser.
Part 2
In part 2 I will go into more depth about how to use ASP and explain about
sending output to the user, variables and some other commands you can use.
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ASP Tutorial |