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I have been quite busy lately, trying to design and code my site (far from done XD).

And after
having learned how to make a simple login, I will try to write my own tutorial, for you

the tutorial
Step 1:
The first step in designing a member system is to plan out exactly what you need. A common
impulse among programmers is to jump right in and start coding. I'll be honest and admit that I'm
guilty of this more so than anyone. However, since I'm in control of this conversation (yes!),
you'll have it all planned out by reading through this before you even see any code.

What will you need to start?

First of all, you need a server that supports a CGI or Server-side language. For this tutorial, it's
PHP. I won't be directing any attention to any other language at this time, so although the
concepts will be similar, the code will be entirely different than something you might use in Perl
or ASP. As a side note, it is possible to perform a member system simply using JavaScript, but it
would not be remotely secure because JavaScript is client-side (thus able to be viewed by
anyone), and even if you had a one-way encryption script it would not be feasible because of the
pain of hard-coding usernames and encrypted passwords into the HTML document.

Second, at least for our purposes, you need a database. Preferably MySQL. PHP and MySQL go
hand-in-hand, so a lot of servers tend to match the two up. Thus, since we're talking PHP, we
may as well talk MySQL.

Third, you will need 4 blank PHP web pages entitled: register.php, login.php, members.php, and
logout.php. After you have these pages created and open, we're ready to start.

Step 2: Database

If we want to design a members system, we'll need a database. So all we need to do in this step is
to create the table we will use to manage the user's login information. Note that the schema we
use here is quite simple, and is only simplified to help you see how it works.
Name the table "dbUsers." It will need 4 fields:

[I]Name Type Addition[/I]

id int(10) Primary Key, AUTO_INCREMENT
username varchar(16) Unique
password char(16)
email varchar(25)

Once you've made the database table, you're ready to design and code the registration page.

Create a File to Connect to your Database

Create a new file and name it dbConfig.php. This file will contain the PHP code that will connect
to the MySQL database, and select the correct database. Make sure you have added users to your
MySQL database with read/write or admin access, then place this type of code into the
dbConfig.php file:
// Replace the variable values below
// with your specific database information.
$host = "localhost";
$user = "UserName";
$pass = "Password";
$db = "dbName";

// This part sets up the connection to the

// database (so you don't need to reopen the connection
// again on the same page).
$ms = mysql_pconnect($host, $user, $pass);
if ( !$ms )
echo "Error connecting to database.\n";

// Then you need to make sure the database you want

// is selected.

Step 3: Register


On your registration page, you need to create a web form that will allow the user to plugin a
username, password, and their e-mail address. Then, also on your page, add code that runs only
when information has been passed via the form. Finally, display a "Registration Successful!"
message to the user.

// dbConfig.php is a file that contains your

// database connection information. This
// tutorial assumes a connection is made from
// this existing file.
include ("dbConfig.php");

//Input vaildation and the dbase code

if ( $_GET["op"] == "reg" )
$bInputFlag = false;
foreach ( $_POST as $field )
if ($field == "")
$bInputFlag = false;
$bInputFlag = true;
// If we had problems with the input, exit with error
if ($bInputFlag == false)
die( "Problem with your registration info. "
."Please go back and try again.");

// Fields are clear, add user to database

// Setup query
$q = "INSERT INTO `dbUsers` (`username`,`password`,`email`) "
."VALUES ('".$_POST["username"]."', "
."PASSWORD('".$_POST["password"]."'), "
// Run query
$r = mysql_query($q);

// Make sure query inserted user successfully

if ( !mysql_insert_id() )
die("Error: User not added to database.");
// Redirect to thank you page.
Header("Location: register.php?op=thanks");
} // end if

//The thank you page

elseif ( $_GET["op"] == "thanks" )
echo "<h2>Thanks for registering!</h2>";

//The web form for input ability

echo "<form action=\"?op=reg\" method=\"POST\">\n";
echo "Username: <input name=\"username\" MAXLENGTH=\"16\"><br />\n";
echo "Password: <input type=\"password\" name=\"password\"
echo "Email Address: <input name=\"email\" MAXLENGTH=\"25\"><br />\n";
echo "</form>\n";
// EOF
Step 4: Login


Now in PHP, first we need to check the username and password against the information stored in
the database. Since when the user registered, we encrypted their password using the MySQL
PASSWORD() function, we re-encrypt the password the user supplied in the login form and
cross-check this with the existing value in the dBase. If login information is O.K., then we need
to use sessions to store the user's ID so they can access member-only content.
// dBase file
include "dbConfig.php";

if ($_GET["op"] == "login")
if (!$_POST["username"] || !$_POST["password"])
die("You need to provide a username and password.");

// Create query
$q = "SELECT * FROM `dbUsers` "
."WHERE `username`='".$_POST["username"]."' "
."AND `password`=PASSWORD('".$_POST["password"]."') "
."LIMIT 1";
// Run query
$r = mysql_query($q);

if ( $obj = @mysql_fetch_object($r) )
// Login good, create session variables
$_SESSION["valid_id"] = $obj->id;
$_SESSION["valid_user"] = $_POST["username"];
$_SESSION["valid_time"] = time();

// Redirect to member page

Header("Location: members.php");
// Login not successful
die("Sorry, could not log you in. Wrong login information.");
//If all went right the Web form appears and users can log in
echo "<form action=\"?op=login\" method=\"POST\">";
echo "Username: <input name=\"username\" size=\"15\"><br />";
echo "Password: <input type=\"password\" name=\"password\" size=\"8\"><br
echo "<input type=\"submit\" value=\"Login\">";
echo "</form>";

Step 5: Members Area


Now that the user has logged in successfully, and has his id, username, and login stored in
session variables, we can start working with member-only content. A major thing to remember is
that any page you want to carry session data over to you must declare a session_start(); at the top
of your code.

if (!$_SESSION["valid_user"])
// User not logged in, redirect to login page
Header("Location: login.php");

// Member only content

// ...
// ...
// ...

// Display Member information

echo "<p>User ID: " . $_SESSION["valid_id"];
echo "<p>Username: " . $_SESSION["valid_user"];
echo "<p>Logged in: " . date("m/d/Y", $_SESSION["valid_time"]);

// Display logout link

echo "<p><a href=\"logout.php\">Click here to logout!</a></p>";

Step 6: Logout


Ah, although it would be nice if our user's never left our web sites, we should give them to
opportunity to log out and destroy the session variables if they so choose. It's quite easy to do,
and you can just copy and paste this one.

// Logged out, return home.
Header("Location: index.php");

That's about it!. I used many simple examples hoping that you will learn how the internal
systems work so you can expand on them and design a system that's just right for your needs.
Have fun!