Forms and User Input
Even with the growth in Web 2.0 Ajax techniques, most people still interact with web sites using forms. They are a tried and tested means of obtaining user input and are likely to retain an important position for a long time to come.
Receiving user input is all well and good—that’s the easy part. But turning that input into usable and secure data is another matter. In this chapter, you’ll find a collection of solutions for helping you with expression evaluation, validation of credit card details, e-mail addresses and text strings, identifying spam, preventing automated input from “bots,” and ways of supporting user-supplied ...