Login Appication using Codeigniter | Learning Curve- Perfect Tutorial for the beginers

How to create a Login module in codeigniter.

After downloading all files from (codeigniter.zip) from CI website

You can create all files inside the application folder inside the CI.

Steps for Creating Login Application

1.Create a database in mysql using phpmydmin.After installling the xaamp/Waamp Type the below url into the browser.

http://localhost/phpmyadmin/

# create a database called testlogin.
# create table users inside the the db testlogin.for creating table users you can use the following queries

CREATE TABLE IF NOT EXISTS `users` (
  `id` tinyint(4) NOT NULL AUTO_INCREMENT,
  `username` varchar(10) NOT NULL,
  `password` varchar(100) NOT NULL,
  PRIMARY KEY (`id`)
)

CREATE TABLE IF NOT EXISTS `users` (

`id` tinyint(4) NOT NULL AUTO_INCREMENT,

`username` varchar(10) NOT NULL,

`password` varchar(100) NOT NULL,

PRIMARY KEY (`id`)

)

# insert the value with username=vasanthan and password=vasanthan

2.configure the routes.php in config folder.

sets the default_controller as like below.
$route[‘default_controller’] = “testlogindisplay”;

3.Change the values inside the database.php file inside the config folder

$active_group = 'default';
$active_record = TRUE;

$db['default']['hostname'] = 'localhost';
$db['default']['username'] = 'root';
$db['default']['password'] = '';
$db['default']['database'] = 'testlogin';
$db['default']['dbdriver'] = 'mysql';
$db['default']['dbprefix'] = '';
$db['default']['pconnect'] = TRUE;
$db['default']['db_debug'] = TRUE;
$db['default']['cache_on'] = FALSE;
$db['default']['cachedir'] = '';
$db['default']['char_set'] = 'utf8';
$db['default']['dbcollat'] = 'utf8_general_ci';
$db['default']['swap_pre'] = '';
$db['default']['autoinit'] = TRUE;
$db['default']['stricton'] = FALSE;

$active_group = 'default';

$active_record = TRUE;

$db['default']['hostname'] = 'localhost';

$db['default']['username'] = 'root';

$db['default']['password'] = '';

$db['default']['database'] = 'testlogin';

$db['default']['dbdriver'] = 'mysql';

$db['default']['dbprefix'] = '';

$db['default']['pconnect'] = TRUE;

$db['default']['db_debug'] = TRUE;

$db['default']['cache_on'] = FALSE;

$db['default']['cachedir'] = '';

$db['default']['char_set'] = 'utf8';

$db['default']['dbcollat'] = 'utf8_general_ci';

$db['default']['swap_pre'] = '';

$db['default']['autoinit'] = TRUE;

$db['default']['stricton'] = FALSE;

4.create a model file in the model folder-user.php

<?php
Class User extends CI_Model
{
 function login($username, $password)
 {
   $this -> db -> select('id, username, password');
   $this -> db -> from('users');
   $this -> db -> where('username', $username);
   $this -> db -> where('password',$password);
   $this -> db -> limit(1);

   $query = $this -> db -> get();

   if($query -> num_rows() == 1)
   {
     return $query->result();
   }
   else
   {
     return false;
   }
 }
}
?>

<?php

Class User extends CI_Model

{

function login($username, $password)

{

$this -> db -> select('id, username, password');

$this -> db -> from('users');

$this -> db -> where('username', $username);

$this -> db -> where('password',$password);

$this -> db -> limit(1);

$query = $this -> db -> get();

if($query -> num_rows() == 1)

{

return $query->result();

}

else

{

return false;

}

4.we can create contorllers inside the controller folder. create the two files in the controller-testlogindisplay.php,homedisplay.php,verifylogindisplay.php

testlogindisplay.php

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Testlogindisplay extends CI_Controller {

 function __construct()
 {
   parent::__construct();
 }

 function index()
 {
   $this->load->helper(array('form'));
   $this->load->view('testlogindisplay');
 }

}
?>

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Testlogindisplay extends CI_Controller {

function __construct()

{

parent::__construct();

}

function index()

{

$this->load->helper(array('form'));

$this->load->view('testlogindisplay');

}

homedisplay.php

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
session_start(); //we need to call PHP's session object to access it through CI
class Homedisplay extends CI_Controller {

 function __construct()
 {
   parent::__construct();
 }

 function index()
 {
   if($this->session->userdata('logged_in'))
   {
     $session_data = $this->session->userdata('logged_in');
     $data['username'] = $session_data['username'];
     $this->load->view('admindisplay', $data);
   }
   else
   {
     //If no session, redirect to login page
     redirect('testlogindisplay', 'refresh');
   }
 }

 function logout()
 {
   $this->session->unset_userdata('logged_in');
   session_destroy();
   redirect('homedisplay', 'refresh');
 }

}

?>

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

session_start(); //we need to call PHP's session object to access it through CI

class Homedisplay extends CI_Controller {

function __construct()

{

parent::__construct();

}

function index()

{

if($this->session->userdata('logged_in'))

{

$session_data = $this->session->userdata('logged_in');

$data['username'] = $session_data['username'];

$this->load->view('admindisplay', $data);

}

else

{

//If no session, redirect to login page

redirect('testlogindisplay', 'refresh');

}

function logout()

{

$this->session->unset_userdata('logged_in');

session_destroy();

redirect('homedisplay', 'refresh');

}

verifylogindisplay.php

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Verifylogindisplay extends CI_Controller {

 function __construct()
 {
   parent::__construct();
   $this->load->model('user','',TRUE);
 }

 function index()
 {
   //This method will have the credentials validation
   $this->load->library('form_validation');

   $this->form_validation->set_rules('username', 'Username', 'trim|required|xss_clean');
   $this->form_validation->set_rules('password', 'Password', 'trim|required|xss_clean|callback_check_database');

   if($this->form_validation->run() == FALSE)
   {
     //Field validation failed.  User redirected to login page
     $this->load->view('testlogindisplay');
   }
   else
   {
     //Go to private area
     redirect('homedisplay', 'refresh');
   }

 }

 function check_database($password)
 {
   //Field validation succeeded.  Validate against database
   $username = $this->input->post('username');

   //query the database
   $result = $this->user->login($username, $password);

   if($result)
   {
     $sess_array = array();
     foreach($result as $row)
     {
       $sess_array = array(
         'id' => $row->id,
         'username' => $row->username
       );
       $this->session->set_userdata('logged_in', $sess_array);
     }
     return TRUE;
   }
   else
   {
     $this->form_validation->set_message('check_database', 'Invalid username or password');
     return false;
   }
 }
}
?>

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Verifylogindisplay extends CI_Controller {

function __construct()

{

parent::__construct();

$this->load->model('user','',TRUE);

}

function index()

{

//This method will have the credentials validation

$this->load->library('form_validation');

$this->form_validation->set_rules('username', 'Username', 'trim|required|xss_clean');

$this->form_validation->set_rules('password', 'Password', 'trim|required|xss_clean|callback_check_database');

if($this->form_validation->run() == FALSE)

{

//Field validation failed. User redirected to login page

$this->load->view('testlogindisplay');

}

else

{

//Go to private area

redirect('homedisplay', 'refresh');

}

function check_database($password)

{

//Field validation succeeded. Validate against database

$username = $this->input->post('username');

//query the database

$result = $this->user->login($username, $password);

if($result)

{

$sess_array = array();

foreach($result as $row)

{

$sess_array = array(

'id' => $row->id,

'username' => $row->username

);

$this->session->set_userdata('logged_in', $sess_array);

}

return TRUE;

}

else

{

$this->form_validation->set_message('check_database', 'Invalid username or password');

return false;

}

5.create view files inside the application/views folder-admindisplay.php,testlogindisplay.php

admindisplay.php

<html xmlns="http://www.w3.org/1999/xhtml">
 <head>
   <title>Login Demo-Admin Area</title>
 </head>
 <body>
   <h1>Home</h1>
   <h2>Welcome <?php echo $username; ?>!</h2>
   <a href="homedisplay/logout">Logout</a>
 </body>
</html>

<head>

<title>Login Demo-Admin Area</title>

</head>

<body>

<h2>Welcome <?php echo $username; ?>!</h2>

<a href="homedisplay/logout">Logout</a>

</body>

</html>

testlogindisplay.php

<html xmlns="http://www.w3.org/1999/xhtml">
 <head>
   <title>Login Demo</title>
 </head>
 <body>
   <h1>Simple Login with CodeIgniter</h1>
   <?php echo validation_errors(); ?>
   <?php echo form_open('verifylogindisplay'); ?>
     <label for="username">Username:</label>
     <input type="text" size="20" id="username" name="username"/>
     <br/>
     <label for="password">Password:</label>
     <input type="password" size="20" id="passowrd" name="password"/>
     <br/>
     <input type="submit" value="Login"/>
   </form>
 </body>
</html>

<head>

<title>Login Demo</title>

</head>

<body>

<h1>Simple Login with CodeIgniter</h1>

<?php echo validation_errors(); ?>

<?php echo form_open('verifylogindisplay'); ?>

<label for="username">Username:</label>

<br/>

<label for="password">Password:</label>

<br/>

</form>

</body>

</html>