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

Implementing User Authentication
585
Listing 27.11
display_user_menu();
do_html_footer();
?>
Continued
You might recognize the logic in the member.php script: It reuses some of the ideas from
Chapter 23.
First, you check whether the user has come from the front page—that is, whether he
has just filled in the login form—and try to log him in as follows:
if ($username && $passwd) {
// they have just tried logging in
try {
login($username, $passwd);
// if they are in the database register the user id
$_SESSION['valid_user'] = $username;
}
You try to log the user in by using a function called login(). It is defined in the
user_auth_fns.php library, and we look at the code for it shortly.
If the user is logged in successfully, you register his session as you did before, storing
the username in the session variable valid_user.
If all goes well, you then show the user the members page:
do_html_header('Home');
check_valid_user();
// get the bookmarks this user has saved
if ($url_array = get_user_urls($_SESSION['valid_user'])) {
display_user_urls($url_array);
}
// give menu of options
display_user_menu();
do_html_footer();
This page is again formed using the output functions. Notice that the page uses several
other new functions: check_valid_user() from user_auth_fns.php, get_user_urls()
from url_fns.php, and display_user_urls() from output_fns.php.The
check_valid_user() function checks that the current user has a registered session.
This is aimed at users who have not just logged in, but are mid-session.The
get_user_urls() function gets a user’s bookmarks from the database, and
display_user_urls() outputs the bookmarks to the browser in a table.We look at
check_valid_user() in a moment and at the other two in the section on bookmark
storage and retrieval.