Buggy Brain

In this article I’ll try to describe how to develop a very simple Content Management System (CMS). I’ve chosen PHP as the server-side scripting language and MySQL as the database management system purely because I think they are fairly easy to use and they do the job very well.

I won’t spend any time describing CMSs, what they are, or why you should or should not use them as there are plenty of excellent articles around that describe them perfectly well. I’ll just explain one way of developing a CMS.

This CMS consists of a single web page (index.php) that can have its contents updated by use of a form (editPage.php). The contents entered via the form are stored in a database, and are accessed and displayed by the web page. Although this CMS is too simple to be of any real use, it could be used as the starting point for a real life CMS solution.

There are four files in this project:

cms.sql
editPage.php
updatePage.php
index.php

cms.sql
This file creates a database called cms, and creates a table in that database called page. It also loads some intial data into the table. You only need to use this file once.

editPage.php
This web page contains a simple form that can be used to enter (and edit) the contents displayed by index.php.

updatePage.php
This is the form handler – the script that processes the data (entered in editPage.php) and inserts it into the database table (page).

index.php
This is the web page that displays the data held in the database table.

cms.sql

1. CREATE DATABASE cms;
2. USE cms;
3. CREATE table page (
4. pageID integer auto_increment,
5. contents text,
6. primary key (pageID)
7. );
8. insert into page (pageID, contents) values (’1′, ‘dummy text’);

Line 1 creates a database called cms in the MySQL database management system.

Line 2 tells MySQL to use the database for the subsequent commands.

Line 3 creates a table in the database.

Line 4 creates a column called pageID, which will contain integers, and which will be automatically incremented as new records are added to the table. As we only have one web page (index.php) in our imaginary website, we will only have one record and therefore one integer: 1. If we added additional pages to the table, they would be automatically numbered (2, 3, 4, etc).

Line 5 creates a second column called contents, which will contain text. This is where the editable contents displayed by index.php will be stored.

Line 6 sets pageID as the primary key, which you can think of as a reference for the table. As we only have one table, which will contain only one record, we won’t make any use of the key. I’ve included it though because it’s good practice to do so.

Line 7 simply closes the bit of code that was started in line 3.

Line 8 inserts some intial data into the table: 1 as the first (and only) pageID, and ‘dummy text’ as the contents of the first record.

editPage.php

(Note that for display considerations, I’ve used square brackets ‘[' instead of angle brackets for tag names.)

1. [html]
2. [head]
3. [title]Really Simple CMS[/title]
4. [/head]
5. [body]
6. [h1]Really Simple CMS[/h1]
7. [?php
8. mysql_connect("localhost", "root", "password");
9. $result = @mysql_query("SELECT contents from cms.page");
10. while ($row = mysql_fetch_assoc($result)){
11. $contents = $row['contents']; // Do not change these to angle brackets
12. }
13. ?]
14. [form name="form1" method="post" action="updatePage.php"]
15. Enter page content:[br][textarea rows="10" cols="60" name="contents"][?php echo "$contents" ?][/textarea]
16. [input type="submit" name="Submit" value="Update Page"]
17. [/form]
18. [/body]
19. [/html]

Most of this file is fairly simple HTML that doesn’t need explaining. However, the following bits of code are probably worth discussing.

Lines 7 through to 13 contain PHP code to connect to the database and extract the contents of the web page.

Line 15 contains a tiny bit of PHP code to display the contents in the form’s textarea. This line shows how easy it is to integrate bits of PHP code into lines of HTML code.

Remember though that in order to use PHP code in an HTML page, the file has to have an extension of .php. If it does not, the PHP code will not be processed by the web server.

updatePage.php

1. [?php
2. $contents=$_REQUEST['contents']; // Do not change to angle brackets
3. mysql_connect(”localhost”, “root”, “password”);
4. $result = @mysql_query(”UPDATE cms.page SET contents=’$contents’”);
5. mysql_close();
6. ?]

This is the form handler, that’s to say, the script that processes the data entered into the form (in editPage.php).

Line 1 signifies the start of a PHP script.

Line 2 requests the contents that were posted from the form. We could have written
$contents=$_POST['contents']; instead if we had wanted to.

Line 3 connects to the MySQL database server, setting up the host name, which I’ve assumed to be localhost, the database user, which I’ve assumed to be root, and the password needed to connect to the database. Naturally, I have no idea what this would be for your system so I’ve just written the word password.

Line 4 updates the page table in the cms database with the new contents.

Line 5 closes the database connection.

Line 6 closes the PHP script.

index.php

1. [html]
2. [head]
3. [title]Home Page[/title]
4. [body]
5. [h1]Home Page[/h1]
6. [?php
7. mysql_connect("localhost", "root", "password");
8. $result = mysql_query("select contents from cms.page");
9. while ($row = mysql_fetch_assoc($result)){
10. $contents = $row['contents']; // Do not change to angle brackets
11. }
12. echo $contents;
13. ?]
14. [/body]
15. [/html]

This is the web page that displays the contents from the database.

Most of the lines in this web page are pretty straight forward and don’t need explaining. Lines 6 to 13 contain the PHP script that extracts the contents from the database and displays (echos) it in the browser.

Installing/Running the CMS

To use the CMS you need to copy the files onto your web server into the area allocated for web pages. Your web server needs to support PHP and MySQL; if it doesn’t, the CMS won’t work.

You also need to use the correct database connection names and passwords (those used in the mysql_connect lines in the PHP scripts).

Exactly how you run the cms.sql file to set up the database and database table will vary from web server to web server so it’s difficult to give precise instructions here. If you have a phpMyAdmin icon or something similar in your web servers control/administration panel you should be able to use that.

Once you’ve set up the database and table, you can simply browse to the editPage.php web page and update the database contents. You can then browse to the index.php page to view the updates.

Watch the video related to Php Scripts

Help answer the question about Php Scripts

I want to add a form to my site, to collect some data and an image. Any free php scripts?
It's a simple form, and i need users to upload an image.
I need a form generator…
anyone?

About Author

John Dixon is a web developer working through his own company John Dixon Technology. As well as providing web development services, John’s company also provides free open source accounting software written in PHP and MySQL.

This entry was posted on Friday, April 18th, 2008 at 1:16 pm and is filed under Scripts. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.