PHP and MySQL for Dynamic Web Sites: Visual QuickPro Guide

What Are Arrays?

The final variable type I’ll introduce in this book is the array. Unlike strings and numbers (which are scalar variables, meaning they are single-valued), an array can hold multiple, separate pieces of information. An array is therefore like a list of values, each value being a string or a number or even another array.

Arrays are structured as a series of key-value pairs. For each item in the list, there is a key (or index) associated with it. The resulting structure is not unlike a spreadsheet or database table (Table 2.2).

Table 2.2. The $artists array uses numbers for its keys.

Array Example 1: $artists
KEY	VALUE
0	Low
1	Aimee Mann
2	Ani DiFranco
3	Spiritualized
4	Air

PHP supports two kinds of arrays: indexed, which use numbers as the ...