Chapter 5. Form Validation and Security
In this chapter, we will cover:
Making "required" fields
Specifying the types of input that are allowed, that is, text, numbers, dates, and so on
Customizing validation error messages
Adding extra security with server-side validation of submitted information
Getting the user to confirm their data before submission
Adding an ImageVerification captcha/anti-spam check
Adding a ReCaptcha anti-spam check
Limiting form access to registered users