Designer-Friendly Scalable PHP Applications

PHP is a really popular web applications development language that is very accessible to both amateur and advanced programmers. Unfortunately many php developers have not received much formal training or experience in software development, so there's a lot of scary PHP code out there that is really hard to maintain and extremely difficult to customize look and feel.

It sort of goes without saying that writing code and making web pages look good are two very different skill sets. I'm a decent coder, but don't ask me to use photoshop or do CSS. When I write an application I turn over to design experts to make it look pretty. So as a rule, I want to let them do their job exposing them to as little of the PHP code as possible. As a result, they don't waste time reading code they can't modify and there is much less risk of a design change breaking your application.

What follows is a list of "Best Practices" that I use when I write PHP applications:

• Keep as little PHP as possible in the "front-end" page
• Put all your post processing code in a code-behind page.
• Separate SQL logic from application logic.
• Use database agnostic library such as ADODB or PEARDB. (I prefer ADODB)
• Wrap all complex "rendering" in functions.
• Put as little look and feel into your application as possible, let the desgners create CSS to give look and feel. Without the CSS your applications should look ugly!

Application Example

The sample application is tracking a list of URL's in a database. The page that we'll examine in particular is that page that "adds a link" to the list of links in a container. Categories are added into the table assuming the user entered comma separated valued list of categories for this bookmark.