not responding while login - function

Question

I am new to CodeIgniter, and am trying to write code to log in after registering using a username and password in registration form using a PHPMyAdmin database. I am not getting anything when I try to log in, and it doesn't display an error or any message.
public function login() {
$this->form_validation->set_rules('username','Username','required');
$this->form_validation->set_rules('password' , 'Password');
if($this->form_validation->run() == TRUE){
//check user in database
$this->db->select('username' , 'password');
$this->db->from('user_register');
$this->db->where(array('username' => $username, 'password' => $password));
$query = $this->db->get();
$user = $query->row();
if($user->email){
$this->session->set_flashdata("Successful login");
$_SESSION['user_logged'] = TRUE;
$_SESSION['username'] = $user->username;
} else {
$this->session->set_flashdata("Error No such record found");
}
}
// load view and showing login form
$this->load->view('login');
}

Answer 1

First, you should read the documentation, looks like you skip that part, but it's very important!
Let's code a little bit and fix the bugs!
User data
Well, users will enter their data and we will check, if evertyhing is correct, we can redirect user to the protected page. You call for variables (see Query:) but you I'm not seeing on your code. You should put like that, before your query job
$username = $this->input->post("username");
$password = $this->input->post("password");
Now, you will be able to use the where to get the user data. =)
Query:
If read about OOP with PHP, you know that when you pass parameters to a method, each parameter have their own "action". In case of the select method, you should keep the data you want to select, on the same quote, because you the way you do, it's like you passing multiple parameters to the method.
$this->db->select('username, password');
$this->db->from('user_register');
$this->db->where(array('username' => $username, 'password' => $password));
First, to decide if the record exist or not, I prefer this way:
if($query->num_rows() > 0) {
$user_data = $query->row();
// We should verify if the user entered the password that correspond to the account.
// If not, we tell them that the password is incorrect.
if($password != $user_data->password) {
$this->session->set_flashdata("error", "Wrong password!");
return redirect(site_url());
}
// You can use the CI built in methods to work with sessions
$this->session->set_userdata(array(
'username' => $user_data->username,
));
$this->session->set_flashdata("success", "You are logged in!");
return redirect(site_url());
} else {
$this->session->set_flashdata("Error: No such record found");
redirect(site_url());
}
Flash data
Yeah, we use flashdata to show a message for the user. But, you should pass an item and the value of this item. Like that:
$this->session->set_flashdata('success', 'Successfully logged in!");
And, to retrieve the data on your views, you can do like...
<?php
$success = $this->session->flashdata("success");
$error = $this->session->flashdata("error");
if(!empty($success)) {
echo $success;
}
if(!empty($success)) {
echo $error;
}
?>
Recommendations
Sessions: https://codeigniter.com/userguide3/libraries/sessions.html
Database: https://www.codeigniter.com/userguide3/database/query_builder.html
Also, I recommed you, to take a minute on YouTube, to understand CodeIgniter.
If I forgot something, let me know! =)

Answer 2

Great Suggestion by webmasterdro's Answer.
I would like to extend it a little bit.
Looking at your code it looks like you have added the query to the controller.
And as a suggestion, if you are using an MVC framework then try to follow some basic MVC flow. because if you are not following that then it will be useless to use a framework.
User Controller to handle the post data and validations.
Use model to do the database query.
Use __construct for loading the common model or libraries.
Do not save plane password use md5 or other encryption technique.
Store User detail to the session which you can use further in after login.
Codeigniter has a great user guide. Try to follow that.
So, your code Should be your like this below.
Controller:
public function __construct() {
parent::__construct();
// Load model
$this->load->model('login_database');
}
public function your_controller_function_name() {
// Check validation for user input in SignUp form
$this->form_validation->set_rules('username', 'Username', 'trim|required|xss_clean');
$this->form_validation->set_rules('password', 'Password', 'trim|required|xss_clean');
if ($this->form_validation->run() == FALSE) {
$this->load->view('login_form_view');
} else {
$username = $this->input->post("username");
$password = $this->input->post("password");
$result = $this->login_database->registration_insert($username, $password);
//You can do this also if($result != FALSE)
if (!empty($result)) {
// You can set other data to the session also form here
$session_data = array(
'username' => $result['user_name']
);
// Add user data in session
$this->session->set_userdata('logged_in', $session_data);
// You can set flash data here
$this->load->view('your_view');
} else {
$data = array(
'error_message' => 'Invalid Username or Password'
);
$this->load->view('your_login_form_view', $data);
}
}
}
Model:
// Read data using username and password
public function login($username, $password) {
$this->db->select('username');
$this->db->from('user_register');
$this->db->where(array('username' => $username, 'password' => $password));
$query = $this->db->get();
$user_data = $query->row_array();
if ($query->num_rows() == 1) {
return user_data;
} else {
return false;
}
}
I have not added detail related to flash data because the previous answer has explained it properly.