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Why work harder when you can just work smarter, and get things done in half the
time? One of PHP's many uses is in creating templates, which allow you to
separate content and formatting. The benefits of this are immediately
obvious - you can change the look of an entire site by just editing a single
line of code, and with more advanced usage of mySQL, you can even create whole sites
that run on a single file. To get you started down the slippery slope of
templating systems, here's an explanation of the theory behind their creation,
and three different ways to implement them on your
website:
The Theory Behind PHP Templates
Imagine, if you will, that your
website is an automated sandwich-making machine pre-filled with one type of
bread. To make a sandwich you simply would add the filling, and then let
the machine add the bread (which is always the same), thus making your tasty
snack. A website is no different - there are parts of your pages which
will always remain the same (i.e. the menu, header, footer, etc), and then
there's the content, which will be different from page to page. The whole
aim of PHP templates is to isolate the static content from the variable content,
and then dynamically slap them together when a visitor requests the pages in
their browser. This creates highly desirable URLs such as:
http://www.yourdomain.com/index.php?p=yourpage
Two of the following methods will utilize the above URL to create the exactly
the same page, albeit with different methods. The pros and cons of each
method will be discussed in turn.
Central Content Include
With this template technique, you define the
static page structure in one file, index.php, and then dynamically include the
variable
content specified in the URL string. The code is as follows:
<?php
$page = $_GET['p'];
if (($page == "news") or ($page =="")) { include('news.php');
} else if($page == "tutorials") { include('tutorials.php');
} else if($page == "downloads") { include('downloads.php');
} else if($page == "faqs") { include('faqs.php');
} else if($page == "links") { include('links.php');
} else if($page == "legalinfo") { include('legalinfo.php');
} else if($page == "privacy") { include('privacy.php');
} else { include('404error.php');
}
?> |
This code is remarkably easy to understand, even for somebody completely new to
programming. Essentially what it does is extract the value of p in
the URL, and then tries to match it to a value in a logical list of files. If
p is not set, it loads the contents of a default file instead - in this
case I've set it to news.php. If a non-sensical p value is entered,
the 404error.php page is output. This is a very simple template
method, and the one which we use here at Biorust. As a disadvantage,
though, its impossible to add variables inside the included file which affect
the static design above the include. This prevents you, for example,
having a different page title depending on content.
Header & Footer Include
If the complex types of URL do not appeal to
you, or greater flexibility is needed, header & footer includes may be the way
to go. In an exact opposite fashion to central content includes, this type
of template dynamically adds in the static content at load-time, as opposed to
the variable content. The code is as follows:
<?php
include "header.php";
?>
YOUR CONTENT
<?php
include "footer.php";
?> |
Unlike the other templating techniques, this method will give you normal URLs
(i.e.
http://www.yourdomain.com/yourfile.php), but by adding PHP code above the
page it will also let you alter static design at load time too (so you'd be able
to have different page titles per page, etc). As a disadvantage, this
method generates a lot of files, which can be rather confusing as your site
grows.
Complex Templates
If you desire maximum functionality, variable
'skins', and a totally dynamic design, try combining the two techniques above to
create a complex type of design. I won't go into detail on how to create
these kind of templates here, as this is mainly a tutorial for novices only, but
I will mention that with this technique you can do everything with your design,
even though it'll be more difficult to update later. You'll also get some
pretty fancy URLs, such as http://www.yourdomain.com/index.php?theme=yourtheme&p=yourpage.
I hope this tutorial has been of some use to you! If you need any more advice,
there's a PHP / HTML /
ASP / JS Forum on Biorust, or you can just e-mail me personally and
I'll see if I can help you out. Have fun! :)
- Tutorial written by Man1c M0g
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