Upgrading to PHP 5

Chapter 10. PHP 5 in Action

Previous chapters demonstrate individual pieces of PHP 5, but this chapter is different. Instead of presenting new material, it combines together multiple features of PHP 5 into a unified program.

Specifically, I present a simple address book application that allows you to add new people and search for existing people. This application is designed to:

• Demonstrate a wide range of new PHP 5 features

• Work completely, even though it’s limited in scope

• Be accessible both over the web and from the command line

• Separate application and presentation logic

Records are limited to first name, last name, and email address, and are stored in an SQLite database. A record can be turned into a Person object, and multiple Persons are stored in an addressBook object.

Since the application needs to work from both the Web and from the command line, you need an easy way to convert records into both HTML and plain text. To facilitate this task, every object is capable of using DOM to create an XML representation of its contents. You then use SimpleXML to manipulate these XML documents into formatted output.

The first section in this chapter covers the database schema, so you know how the records are stored. Parts two and three cover the Person and addressBook classes. These sections use many of PHP 5’s new object-oriented features, including property overloading, visibility, class type hints, and custom object iterators using the IteratorAggregate interface. The classes also ...