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
spotless home service Lake Forest ..A company must earn and keep trust or sales don't... Read More
"How do I improve web site sales figures?" The CEO... Read More
Before you set up any scripts you will need some... Read More
#5 User Satisfaction: Learn what your visitors and site users... Read More
Selecting the Perfect Domain NameThe first issue I have with... Read More
While most marketers are beginning to understand the critical importance... Read More
Mini Websites are the most powerful and cost effective solution... Read More
Affiliate programs are a great way to earn an income... Read More
Functions and Subroutines in ASP If you read... Read More
Optimal website design is the art of logical navigation.It will... Read More
SummaryHere's the scoop on what you must know when designing... Read More
Webmaster tools are vital to becoming both efficient and effective... Read More
Web sites are not just places to sell things; they... Read More
Rosalind wants to share her inspirational poetry with a wider... Read More
The Disability Discrimination Act states that service providers must not... Read More
After years of working with entrepreneurs who developed their first... Read More
Dynamically Update Your Web Pages Via E-MailIf you can Send... Read More
Most web sites are more like stage sets than real... Read More
Spend time planning your Web site. Before you design a... Read More
With the New Year upon us yet again, it's time... Read More
That's right. Your method, behavior and strategy you are now... Read More
I've heard several prominent web marketers mention in their classes... Read More
Web accessibility has so many benefits that I really do... Read More
Losing website sales and traffic is sometimes simply a case... Read More
Knowledge is power.And undoubtedly, it is the key to making... Read More
weekly home cleaning Mundelein ..How many Web Sites did you stumble over telling you... Read More
From early days of www, the Internet sites that are... Read More
An additional benefit of website accessibility is an improved performance... Read More
In this example I have used the map of the... Read More
Functions and Subroutines in ASP If you read... Read More
The Internet is being used by local service business to... Read More
When visitors add your web site to their Favorites or... Read More
One of the most useful features offered by some web... Read More
Can you imagine the hypocrisy of spending thousands of dollars,... Read More
Like any area of business your website needs some effort... Read More
"What's in it for me?" you ask. "Why should I... Read More
The first thing my business consultant (read brother-in-law) asked me,... Read More
The growth in Internet usage around the world is astounding... Read More
Every good Internet business understands the value of conversions versus... Read More
In about the Time it takes to Watch a Reality... Read More
Absolutely everything stems from the purpose of your website -... Read More
Profiles are one of the best kept secrets around regarding... Read More
Fantastico is a 3rd-party cPanel add-on and can be purchased... Read More
You've just finished congratulating your marketing team. After six months... Read More
While studying online for IT investment opportunities, I found that... Read More
Have you ever wondered what challenges are faced by other... Read More
Research reveals three important facts:1) The Internet is one of... Read More
I'm a freelance programmer and somehow I managed to get... Read More
Just like all things in life, the ways to run... Read More
Making a web site is easy. Making a good web... Read More
Web Development |