Session

Learn Session in PHP

Createtable.php

<?php
require_once(‘db.php’);

$sql = “CREATE TABLE users (username varchar(30),password varchar(32))”;

$result = mysql_query($sql);

if($result) echo “Table Created”;
else die(mysql_error());

?>

 

Db.php

<?php

/**
* Connect to the mysql database.
*/
$conn = mysql_connect(“localhost”, “root”, “root”) or die(mysql_error());
mysql_select_db(‘test’, $conn) or die(mysql_error());
?>

 

Login.php

<?php
@session_start();
include(“db.php”);
/**
* Checks whether or not the given username is in the
* database, if so it checks if the given password is
* the same password in the database for that user.
* If the user doesn’t exist or if the passwords don’t
* match up, it returns an error code (1 or 2).
* On success it returns 0.
*/
function confirmUser($username, $password){
global $conn;
/* Add slashes if necessary (for query) */
if(!get_magic_quotes_gpc()) {
$username = addslashes($username);
}

/* Verify that user is in database */
$q = “select password from users where username = ‘$username'”;
$result = mysql_query($q,$conn);
if(!$result || (mysql_numrows($result) < 1)){
return 1; //Indicates username failure
}

/* Retrieve password from result, strip slashes */
$dbarray = mysql_fetch_array($result);
$dbarray[‘password’] = stripslashes($dbarray[‘password’]);
$password = stripslashes($password);

/* Validate that password is correct */
if($password == $dbarray[‘password’]){
return 0; //Success! Username and password confirmed
}
else{
return 2; //Indicates password failure
}
}

/**
* checkLogin – Checks if the user has already previously
* logged in, and a session with the user has already been
* established. Also checks to see if user has been remembered.
* If so, the database is queried to make sure of the user’s
* authenticity. Returns true if the user has logged in.
*/
function checkLogin(){
/* Check if user has been remembered */
//echo “heloo”;
if(isset($_COOKIE[‘cookname’]) && isset($_COOKIE[‘cookpass’])){
$_SESSION[‘username’] = $_COOKIE[‘cookname’];
$_SESSION[‘password’] = $_COOKIE[‘cookpass’];
}

/* Username and password have been set */
if(isset($_SESSION[‘username’]) && isset($_SESSION[‘password’])){
/* Confirm that username and password are valid */
if(confirmUser($_SESSION[‘username’], $_SESSION[‘password’]) != 0){
/* Variables are incorrect, user not logged in */
unset($_SESSION[‘username’]);
unset($_SESSION[‘password’]);
return false;
}
return true;
}
/* User not logged in */
else{
//echo “heloo1”;
return false;
}
}

/**
* Determines whether or not to display the login
* form or to show the user that he is logged in
* based on if the session variables are set.
*/
function displayLogin(){
global $logged_in;
if($logged_in){
echo “<h1>Logged In!</h1>”;
echo “Welcome <b>$_SESSION[username]</b>, you are logged in. <a href=\”logout.php\”>Logout</a>”;
}
else{
?>

<h1>Login</h1>
<form action=”<?php $_SERVER[‘PHP_SELF’]; ?>” method=”post”>
<table align=”left” border=”0″ cellspacing=”0″ cellpadding=”3″>
<tr><td>Username:</td><td><input type=”text” name=”user” maxlength=”30″></td></tr>
<tr><td>Password:</td><td><input type=”password” name=”pass” maxlength=”30″></td></tr>
<tr><td colspan=”2″ align=”left”><input type=”checkbox” name=”remember”>
<font size=”2″>Remember me next time</td></tr>
<tr><td colspan=”2″ align=”right”><input type=”submit” name=”sublogin” value=”Login”></td></tr>
<tr><td colspan=”2″ align=”left”><a href=”registration.php”>Join</a></td></tr>
</table>
</form>

<?php
}
}
/**
* Checks to see if the user has submitted his
* username and password through the login form,
* if so, checks authenticity in database and
* creates session.
*/
if(isset($_POST[‘sublogin’])){
/* Check that all fields were typed in */
if(!$_POST[‘user’] || !$_POST[‘pass’]){
die(‘You didn\’t fill in a required field.’);
}
/* Spruce up username, check length */
$_POST[‘user’] = trim($_POST[‘user’]);
if(strlen($_POST[‘user’]) > 30){
die(“Sorry, the username is longer than 30 characters, please shorten it.”);
}

/* Checks that username is in database and password is correct */
$md5pass = md5($_POST[‘pass’]);
$result = confirmUser($_POST[‘user’], $md5pass);

/* Check error codes */
if($result == 1){
die(‘That username doesn\’t exist in our database.’);
}
else if($result == 2){
die(‘Incorrect password, please try again.’);
}

/* Username and password correct, register session variables */
$_POST[‘user’] = stripslashes($_POST[‘user’]);
$_SESSION[‘username’] = $_POST[‘user’];
$_SESSION[‘password’] = $md5pass;

/**
* This is the cool part: the user has requested that we remember that
* he’s logged in, so we set two cookies. One to hold his username,
* and one to hold his md5 encrypted password. We set them both to
* expire in 100 days. Now, next time he comes to our site, we will
* log him in automatically.
*/
if(isset($_POST[‘remember’])){
setcookie(“cookname”, $_SESSION[‘username’], time()+60*60*24*100, “/”);
setcookie(“cookpass”, $_SESSION[‘password’], time()+60*60*24*100, “/”);
}

/* Quick self-redirect to avoid resending data on refresh */
echo “<meta http-equiv=\”Refresh\” content=\”0;url=$_SERVER[PHP_SELF]\”>”;
return;
}

/* Sets the value of the logged_in variable, which can be used in your code */
$logged_in = checkLogin();
$_SESSION[‘logged_in’] = $logged_in;
//echo $_SESSION[‘logged_in’] ;
displayLogin();
?>

 

Logout.php

<?php
session_start();
include(“db.php”);
//include(“login.php”);

/**
* Delete cookies – the time must be in the past,
* so just negate what you added when creating the
* cookie.
*/
if(isset($_COOKIE[‘cookname’]) && isset($_COOKIE[‘cookpass’])){
setcookie(“cookname”, “”, time()-60*60*24*100, “/”);
setcookie(“cookpass”, “”, time()-60*60*24*100, “/”);
}

?>

<html>
<title>Logging Out</title>
<body>

<?php
if(!isset($_SESSION[‘logged_in’])){
echo “<h1>Error!</h1>\n”;
echo “You are not currently logged in, logout failed. Back to <a href=\”login.php\”>Login</a>”;
}
else{
/* Kill session variables */
unset($_SESSION[‘username’]);
unset($_SESSION[‘password’]);
$_SESSION = array(); // reset session array
session_destroy(); // destroy session.

echo “<h1>Logged Out</h1>\n”;
echo “You have successfully <b>logged out</b>. Back to <a href=\”login.php\”>Login</a>”;
}

?>

</body>
</html>

 

Registration.php

<?php
session_start();
include(“db.php”);

/**
* Returns true if the username has been taken
* by another user, false otherwise.
*/
function usernameTaken($username){
global $conn;
if(!get_magic_quotes_gpc()){
$username = addslashes($username);
}
$q = “select username from users where username = ‘$username'”;
$result = mysql_query($q,$conn);
return (mysql_numrows($result) > 0);
}

/**
* Inserts the given (username, password) pair
* into the database. Returns true on success,
* false otherwise.
*/
function addNewUser($username, $password){
global $conn;
$q = “INSERT INTO users VALUES (‘$username’, ‘$password’)”;
return mysql_query($q,$conn);
}

/**
* Displays the appropriate message to the user
* after the registration attempt. It displays a
* success or failure status depending on a
* session variable set during registration.
*/
function displayStatus(){
$uname = $_SESSION[‘reguname’];
if($_SESSION[‘regresult’]){
?>

<h1>Registered!</h1>
<p>Thank you <b><?php echo $uname; ?></b>, your information has been added to the database, you may now <a href=”login.php” title=”Login”>log in</a>.</p>

<?php
}
else{
?>

<h1>Registration Failed</h1>
<p>We’re sorry, but an error has occurred and your registration for the username <b><? echo $uname; ?></b>, could not be completed.<br>
Please try again at a later time.</p>

<?php
}
unset($_SESSION[‘reguname’]);
unset($_SESSION[‘registered’]);
unset($_SESSION[‘regresult’]);
}

if(isset($_SESSION[‘registered’])){
/**
* This is the page that will be displayed after the
* registration has been attempted.
*/
?>

<html>
<title>Registration Page</title>
<body>

<?php displayStatus(); ?>

</body>
</html>

<?php
return;
}

/**
* Determines whether or not to show to sign-up form
* based on whether the form has been submitted, if it
* has, check the database for consistency and create
* the new account.
*/
if(isset($_POST[‘subjoin’])){
/* Make sure all fields were entered */
if(!$_POST[‘user’] || !$_POST[‘pass’]){
die(‘You didn\’t fill in a required field.’);
}

/* Spruce up username, check length */
$_POST[‘user’] = trim($_POST[‘user’]);
if(strlen($_POST[‘user’]) > 30){
die(“Sorry, the username is longer than 30 characters, please shorten it.”);
}

/* Check if username is already in use */
if(usernameTaken($_POST[‘user’])){
$use = $_POST[‘user’];
die(“Sorry, the username: <strong>$use</strong> is already taken, please pick another one.”);
}

/* Add the new account to the database */
$md5pass = md5($_POST[‘pass’]);
$_SESSION[‘reguname’] = $_POST[‘user’];
$_SESSION[‘regresult’] = addNewUser($_POST[‘user’], $md5pass);
$_SESSION[‘registered’] = true;
echo “<meta http-equiv=\”Refresh\” content=\”0;url=$HTTP_SERVER_VARS[PHP_SELF]\”>”;
return;
}
else{
/**
* This is the page with the sign-up form, the names
* of the input fields are important and should not
* be changed.
*/
?>

<html>
<title>Registration Page</title>
<body>
<h1>Register</h1>
<form action=”<?php echo $_SERVER[‘PHP_SELF’]; ?>” method=”post”>
<table align=”left” border=”0″ cellspacing=”0″ cellpadding=”3″>
<tr><td>Username:</td><td><input type=”text” name=”user” maxlength=”30″></td></tr>
<tr><td>Password:</td><td><input type=”password” name=”pass” maxlength=”30″></td></tr>
<tr><td colspan=”2″ align=”right”><input type=”submit” name=”subjoin” value=”Join!”></td></tr>
</table>
</form>
</body>
</html>
<?php
}
?>

 

Share

Leave a Reply

Your email address will not be published. Required fields are marked *

Time limit is exhausted. Please reload CAPTCHA.