Even if that's the case, there is still plenty
of PHP that you could be using. If you do any sort of web design and
would be willing to learn to use a single PHP function, make it
include().
PHP Includes (for people who don't know PHP)
Those of us in the web development business are more than familiar
with PHP. In fact, most of us are crazy about it (except for those of
us stuck using ASP).
But maybe you haven't used it yet because you aren't a programmer.
Even if that's the case, there is still plenty of PHP that you could
be using. If you do any sort of web design and would be
willing to learn to use a single PHP function, make it
include().
What is an include function?
If you don't have a programming background, the concept of an
"include" function may not make any sense. Different
programmers and languages may call these different things, but the
concept is the same.
When you "include" a file, it's kind of like taking
the contents of a file and putting them inside another. From the
perspective of a web designer (rather than a programmer), it's
analogous to using a FRAME or IFRAME to put another file inside an
HTML file.
In fact, you can even use PHP's include() to do some
of the same things you may be doing with FRAME and IFRAME. More on
that in a bit.
How PHP includes are useful to web designers
One of the classic issues of web design is finding a way to
include a navigation list on all of your site's pages. You can do
this manually, but if the list changes then you have to go through
all your pages and edit them just to add even a single link.
If you have a small site (5 or 10 pages), you probably do this by
hand. As you get more complicated, you may use an editor like
Dreamweaver to create templates
that will automatically update specific areas of all your
pages. Unfortunately, many developers are working in a lot of
different locations and don't always have such software available.
So if you get tired of the editing, you
might cave and start using FRAME and IFRAME to include your
navigation list. This isn't the best choice many times because there
are a lot of cases where these HTML tags are not such a great idea;
if nothing else, they tend to be ugly and are at the mercy of the web
browser.
But if you have PHP available on your
web server, this problem becomes trivial to solve. All you need to
do is create a file that holds your navigation list (name it
menu.html, menu.php, or whatever you want) and then include it in
every page you make for that site.
include()'s syntax
To use an include(), you will use code in the
following form.
<?php
include($string);
?>
Even though the string you specify will include a filename and
possibly a path, it is a
string that you are using as a parameter. I point this out because
the first time I did this, I found that odd give my personal
background in programming. This is actually a good thing
because it means you can use
variables to change the file you include, which will be useful if you
end up doing more advanced things with PHP.
So in most situations, your include()
will work something like this:
<?php
include("/path/to/your/included/files/somefile.php");
?>
Once that bit of code is placed in your
web pages, the contents of somefile.php are evaluated when those
pages are opened. If something.php is just a file with HTML code,
that means that all your web pages will look like you added the
contents that file to every web page's source code when opened in a
web browser.
Some notes on paths
If you've done most of your work in
plain HTML, you may not be familiar with "paths." The
easiest way I know to explain paths is with this analogy: paths are
to operating systems as URLs are to web servers.
For example, on your webserver your
site's path is probably something like
/home/accountname/public_html
but your URL is more like
http://yourserver.tld/~accountname
If you aren't sure what your account's
path is, you should probably ask your web host to find out for sure.
Of course, if you learn a little more PHP you'll be able to figure
this out on your own.
You may be wondering if you could
just use the URL for the file you want to include as the path. In
some situations, the answer is yes. But depending on your server's
settings, this probably won't do what you want it to do anyway. In
other words, if everything isn't in the same directory it's best to
either use full paths or traverse directories using "../"
within your path.
A sample implementation
You may want to use PHP includes in a
way similar to the sample below. First, we will create menu.php.
This will be just a short HTML snippet without any HEAD or BODY tags.
<ul>
<li><a href="page1.php">Page 1</a></li>
<li><a href="page2.php">Page 2</a></li>
<li><a href="page3.php">Page
3</a></li>
<li><a href="page4.php">Page 4</a></li>
</ul>
Next, we'll edit each of our individual
pages to look something like this
<html>
<body>
<div id="nav_menu">
<?php include("menu.php"); ?>
</div>
<div id="main_content">
{main page content}
</div>
</body>
</html>
Once you open such a page in a browser
and view the source, it will look like this
<html>
<body>
<div id="nav_menu">
<ul>
<li><a href="page1.php">Page
1</a></li>
<li><a href="page2.php">Page 2</a></li>
<li><a href="page3.php">Page 3</a></li>
<li><a href="page4.php">Page
4</a></li>
</ul>
</div>
<div id="main_content">
{main page
content}
</div>
</body>
</html>
Can you now see what a useful little
function include() is? By using CSS in addition to PHP,
you can dramatically change the look of your entire site by just
editing a few files.
Conclusion
As I said, if you never learn any other
PHP function, learn include()! This little function is
incredibly powerful when used as a time-saver.
It's also a great introduction to PHP
that will convince almost any web designer to give the rest of PHP a
look. I've often joked that just about anything you'd want to code
in PHP probably already has a function in the standard PHP library. Once you start to use PHP even just casually within
your HTML code, I'd be willing to bet you'll come to the same
conclusion.
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