PHP for the Web: Visual QuickStart Guide, Fourth Edition

6. Control Structures

In This Chapter

Creating the HTML Form 116

The if Conditional 119

Validation Functions 122

Using else 126

More Operators 129

Using elseif 138

The Switch Conditional 142

The for Loop 146

Review and Pursue 150

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 Web sites 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 ...