PHP for the Web: Visual QuickStart Guide, Fifth Edition

6. Control Structures

In This Chapter

Creating the HTML Form

The if Conditional

Validation Functions

Using else

More Operators

Using elseif

The Switch Conditional

The for Loop

Review and Pursue

Control structures—conditionals and loops—are a staple of programming languages. PHP has two conditionals—if and switch—both of which you’ll master in this chapter. Conditionals allow you to establish a test and then perform actions based on the results. This functionality provides the ability to make websites even more dynamic.

The discussion of if conditionals requires introduction of two last categories of operators: comparison and logical (you’ve already seen the arithmetic and assignment operators in the previous chapters). You’ll commonly use these ...