Core PHP Programming, Third Edition

Chapter 4. Functions

Topics in This Chapter

• Declaring a Function

• The return Statement

• Scope

• Static Variables

• Arguments

• Recursion

• Dynamic Function Calls

You probably have noticed the use of several functions in the preceding chapters. Date and print are built-in functions that are always available for you. PHP also allows you to declare your own functions.

Functions expand the idea of repeating a block of code. They allow you to execute a block of code arbitrarily throughout your script. You declare a block of code as a function, and then you are able to call the function anywhere. When calling a function, you pass any number of arguments, and the function returns a value.