Smart Pages Can Add Value to Your Website

Conventional web pages are static. They display the same text, graphics, forms, etc. every time they are called.

Dynamic pages are written, in whole or in part, as they are needed. They are more difficult to design, but they are useful when you need to present different information at different times.

For example, the program that writes this page knows that today's date is Saturday, July 5, 2008 in the MDT time zone. It could select today's events from a calendar, offer a special price for a limited time, or calculate a guaranteed delivery date.

Dynamic pages can be combined with online databases. This is especially useful when the data change frequently, as in catalogs and price lists. As described elsewhere, this avoids many problems that arise when the data are scattered through the website. It also permits catalog entries to be added and deleted by updating the database - the program then constructs the correct number of web pages.

Another common use of dynamic pages is to process user inputs from forms. The program can test for missing or erroneous entries, and it can return different pages depending on the visitor's request.

Examples

A calendar of events for the Albuquerque chapter of the American Guild of Organists (AGO) combines XML data files with PHP interactive programming. Each file describes one event, and new events can be put on the calendar simply by uploading their announcement files. After the event has occurred, a report can be added to the file. When a report is present, the PHP program shows a link in the announcement that brings up the report. The calendar is searchable by date and by type of event. To see the XML, look at one of the data files. Your browser will probably show you the data in outline form. If not, use view source to see what the browser sees. You may also be interested in the Document Type Definition (DTD) that is shared by all of the announcement files. This is the plan for combining the various pieces of information into a program announcement.

The AGO site also has a form for adding events to the calendar. The instruction page shows how the form is laid out. To discourage mischief-making, we send passwords by e-mail. Anyone who is not willing to give his or her e-mail address does not get a password.

This sample from a mortgage broker's web site has two kinds of calculator and an interactive form to pre-qualify for a loan.

A form on the Albuquerque AGO site allows visitors to send e-mail to chapter officers without seeing the officers' e-mail addresses. This preserves the officers' privacy, and the webmaster can update the addresses as needed.

A form on this site compares user-id and password entries to those stored in a database. New users can add themselves to the list, and each user can see only his or her own data.

A library of articles from a church newsletter is easily updated by uploading text files to the web server. The PHP program finds these files and constructs a chronological list of links to the individual articles. When a link is selected, the same program converts the text file to a web page. This does not require any change from the newsletter format except to type the date above the title of the article. If it becomes desirable to provide a formal XML version to exchange with other churches, the PHP program can easily be modified to produce it.

You may need a bulletin board system (BBS) so that visitors to your site can talk with you and with other visitors. The BBS must have a way for you to control what is placed into your site. One way to stay aware of what visitors are posting is to have the BBS e-mail you a copy.

Client-side and Server-side Programming

Some of these interactive features can be executed on the visitor's computer, using languages such as Java and JavaScript. There are advantages to performing them on the web server, however:

• The program always works the same way, regardless of which browser the visitor uses.
• Some visitors turn off Java and JavaScript support for reasons of security.
• Large databases do not have to be passed across the Internet for processing in the browser.
• Confidential information can be kept in a database without sending it to every visitor's browser.
• Server-based programs can keep records to identify which features are popular, which features did not work as intended, etc.
• Server-based programs can use cookies where appropriate. These are short files stored on the visitor's machine that can be written and read by the various parts of a website to pass information between them. For example, a shopping cart program needs to know which visitor has selected an item, but it is cumbersome to ask the visitor for identification every time.

I am currently using PHP as a scripting language and MySQL as a database system for server-side programming. These are open-source programs, meaning that they are available on most web-hosting services at no charge. They are constantly being expanded and improved through the efforts of millions of users world-wide.

Please phone or send e-mail for more information about smart pages.

Copyright 2000-2002 by Thomas David Nichols. All rights reserved.

Return to HQS home

Heliotrope Quality Systems How to reach us

www.hqswebsites.com