this section, we introduce validation on the server. The techniques
described here are typical of those that validate a
<form> after the user has submitted data to
the server. We show how to extend and integrate this approach further
in Chapter 8 so that the batch errors are reported
as part of the customer
<form>, and we show
the completed customer entry
validation in Chapter 10.
In this section, we show how to validate
selected winestore customer
including examples of the validation checks required for mandatory
fields, field lengths, and data types. Many functions—including
the regular expression and string functions—are discussed in
detail in Chapter 2.
Our system requirements in Chapter 1 note the following validation requirements:
A user must provide a surname, first name, one address line, a city, a state, a zip code, a country, a birth date, an email address, and a password.
The user may also optionally provide a middle initial, a title, two additional address lines, a state, a telephone number, and a fax number.
Testing whether mandatory fields have been entered is straightforward, and we have implemented this in our examples in Chapter 6. For example, to test if the user’s surname has been entered, use the following approach:
// Validate the Surname if (empty($formVars["surname"])) // the user's surname cannot be a null string $errorString .= "\n<br>The surname field cannot ...