Chapter4.Object-Oriented Programming

Chapter 4. Object-Oriented Programming

In the previous chapter, we learned about two very powerful methods for grouping and organizing code. In this chapter, we will learn about one more that will be used extensively throughout this bookobject-oriented programming, or the ability to create entirely new types with custom data and implementations.

After this chapter, we will know

• The drawbacks to standard function libraries and how object-oriented programming helps us solve them

• How to declare, implement, and use classes in PHP5

• How to extend classes we have written

• How to create hierarchies of related classes that share implementation and classes that expose common programming 'interfaces'

• Some of the other details and features of classes in PHP