PHP and MySQL Web Development 4th Ed-tqw-_darksiderg

Implementing User Authentication
581
Listing 27.7 filled_out() Function from data_valid_fns.php—This Function
Checks That the Form Has Been Filled Out
function filled_out($form_vars) {
// test that each variable has a value
foreach ($form_vars as $key => $value) {
if ((!isset($key)) || ($value == '')) {
return false;
}
}
return true;
}
Listing 27.8 valid_email() Function from data_valid_fns.php—This Function
Checks Whether an Email Address Is Valid
function valid_email($address) {
// check an email address is possibly valid
if (ereg('^[a-zA-Z0-9_\.\-]+@[a-zA-Z0-9\-]+\.[a-zA-Z0-9\-\.]+$', $address)) {
return true;
} else {
return false;
}
}
The function filled_out() expects to be passed an array of variables; in general, this is
the $_POST or $_GET array. It checks whether the form fields are all filled out, and
returns true if they are and false if they are not.
The valid_email() function uses a slightly more complex regular expression than the
one developed in Chapter 4,“String Manipulation and Regular Expressions,” for validating
email addresses. It returns true if an address appears valid and false if it does not.
After you’ve validated the input data, you can actually try to register the user. If you
look back at Listing 27.6, you can see that you do this as follows:
register($username, $email, $passwd);
// register session variable
$_SESSION['valid_user'] = $username;
// provide link to members page
do_html_header('Registration successful');
echo 'Your registration was successful. Go to the members page to start
setting up your bookmarks!';
do_html_url('member.php', 'Go to members page');
// end page
do_html_footer();