People often have identical sections of code spread throughout many ASP pages, typically code at the top of the page (usually referred to as the header) and the lower part of the page (the footer). Similarly, you may have code that performs a certain set of instructions that you are repeating across multiple pages. Consider an example:-
<%
If foobar="yes" then
response.write "YES!"
Else
response.write "NOT YES!"
End if
%>
Ok, ok... it's simple, but imagine that you used this on multiple pages. What's wrong with this picture?
Well... you don't have to think about that long before realising that if you ever wanted to change something about that piece of code, you'd have your work cut out. you would have to change every page... everyone has done this at some stage and luckily most usually take the steps to learn a way around this problem.
If we could save our valuable chunk of code into a file and have that file accessed whenever we needed the code, then we no longer have a problem when it comes to changing things, as we simply update one file. Include files or Server Side Includes (SSI) as they are more commonly known are a powerful way to not only save time when it comes to maintaining and updating a site, but also increase efficiency and speed of that site too!
Ok, lets see how we use an include file... to start with we need to use one of two methods. The first one allows for including files relatively. By that I mean relative to the directory the ASP file that is using the include file resides. The second method includes files virtually. Including files virtually means that the path is taken from the root directory.
Consider that we are going to have a file (/main/somefile.asp) include another file (/includes/someinclude.asp).
To demonstrate, relative inclusion, look at this:-
<%
Response.Write "executing included code now"
%>
<!--#include file="../includes/someinclude.asp"-->
<%
Response.write "done executing included code"
%>
And here, we give an example of the other method, virtual inclusion:-
<%
Response.Write "executing included code now"
%>
<!--#include virtual="/includes/someinclude.asp"-->
<%
Response.write "done executing included code"
%>
Note the slight difference between the two methods. With virtual inclusion, you can move the file that calls upon the include file anywhere without affecting the outcome, because the path is always relative to the root. The same cannot be said however for relative inclusion. If you move a file that is using relative inclusion to a different directory, you'll most likely find the relative path is no longer correct.
From the examples above, you may also notice that both methods, when calling the include do so OUTSIDE of the ASP script block. This because #include declarations are not interpreted by ASP. Include files are included before a single line of ASP is processed which means the following WONT work:-
%lt;%
Page=request.form("page")
%>
<!--#include file="../includes/<%=page%>.asp"-->
We were attempting to perform a dynamic include and I would be the first to admit that the above would be very useful indeed if in fact it were possible. I do intend to cover a few methods that work around this set back but I know you will now be itching to get started right away on using include files to even worry about this, so I will cover it in a future article.
I hope that you have found the above informative and hope it inspires you all to write code that's more efficient and more easily maintained.
Rob Collyer, experienced with 20 years programming knowledge and site administrator of www.webforumz.com - Copyright 2003-2004
limousine chicago serviceWe are clearly well past the innocent "golden age" of... Read More
Dan Kennedy once said that if you can't make money... Read More
"I have a small business with just a couple of... Read More
Your ObjectiveYour small business needs an appealing and professional website... Read More
Getting a Targeted Visitor to a website is a waste... Read More
Like most average persons, I wanted some extra money to... Read More
If you ever want to create a state directory, article... Read More
Creatively marketing your corporate site takes time in the set... Read More
There are hundreds of millions of Web surfers today. Each... Read More
Did you know that hosting companies overcrowd their servers despite... Read More
One of the biggest mistakes that most online retailers make... Read More
Web sites are not just places to sell things; they... Read More
Selecting the Perfect Domain NameThe first issue I have with... Read More
Many websites I come across don't have a single link... Read More
SummaryHere's the scoop on what you must know when designing... Read More
So your prospect, Mary, is sitting at the computer reading... Read More
How many Web Sites did you stumble over telling you... Read More
Optimize your time. How much time each day must you... Read More
2 Golden Rules for an Engaging Website35% of visitors fail... Read More
If you are developing your website on a host that... Read More
What do you mean, you don't have a website for... Read More
Anyone who knows anything about web accessibility knows that images... Read More
First, using a lot of web graphics, flash, banners and... Read More
Simply ensuring your website is accessible to screen reader users... Read More
Understanding and using web analytics.In recent years, website marketers were... Read More
high bay induction lighting led street lights cost Pete's produce ..Right after the thought, "I need a website," people usually... Read More
There are many elements that are key to successful web... Read More
Most people know they need a website in order to... Read More
Designing an E-commerce Web site is not as simple as... Read More
In 1995 a new era of accessibility for disabled people... Read More
People like to get immediate responses to requests. Autoresponders are... Read More
Have you ever thought the secret behind the success of... Read More
The big thing these days is your ability to capture... Read More
Design and layout can make your communication come alive and... Read More
Does your website have a links/resources page?Do you exchange reciprocal... Read More
The "robots" meta tag, when used properly, will tell the... Read More
SiteSpinnerSiteSpinner is a user-friendly web site development tool that includes... Read More
In the big, wide online world there are millions of... Read More
Web accessibility has so many benefits that I really do... Read More
Is Your Web Site an Expense or an Investment?Why don't... Read More
When building a relationship, listening is more important than talking.A... Read More
When a user signs up at your website, you may... Read More
Creatively marketing your corporate site takes time in the set... Read More
The needs of screen magnifier users are overlooked when implementing... Read More
One of the most important parts of establishing a new... Read More
Most web sites are more like stage sets than real... Read More
Internet has opened a whole new world for web developers... Read More
1. Choose a big enough font size. A size 12... Read More
You've decided to create a website to market your products... Read More
There are several reverse bid freelance sites out there. Beyond... Read More
Web Development Web Development |