如何访问数据库中的数据？ -CodeIgniter

Question

I am using CodeIgniter and have a login system. I am still fairly new with php and I am wondering once the user is logged in, how I can access his/her data to use throughout the site? Right now I am trying to make it say welcome "username" but I dont know where the variables come from and how I should use them. Right now in my home_view.php I have:

    <div class="main">
    <h2>Welcome <?php echo $username; ?>!</h2>
</div>

It throws this error:

A PHP Error was encountered

Severity: Notice

Message: Undefined variable: username

Filename: views/home_view.php

Line Number: 22

Can someone tell me how to do this?

Answer 1

Question: How do you access a logged-in user's data for use throughout the site?

The logged-in user specific data is usually stored in a session. For codeigniter, you can access session data using $this->session->userdata('item'); , or for example $this->session->userdata('username'); .

However, if you are using a specific login system it depends on the login system that you are using .

---

Custom Login System

After receiving the login information from a login form, pass the data to the session using the following:

$newdata = array(
                   'username'  => 'johndoe',
                   'email'     => 'johndoe@some-site.com',
                   'logged_in' => TRUE
               );

$this->session->set_userdata($newdata);

Then refer to the username with the following:

$this->session->userdata('username');

See Adding Custom Session Data in the Codeigniter Documentation.

---

Login System Example

A popular codeigntier authentication library is Tank-Auth .

When using Tank-Auth, after a user is logged in, you can call $this->tank_auth->get_username() (which calls $this->ci->session->userdata('username') , as mentioned above). This can then be stored and passed to a view.

In Tank-Auth you will see:

application/controller/welcome.php

$data['user_id']    = $this->tank_auth->get_user_id();
$data['username']   = $this->tank_auth->get_username();
$this->load->view('welcome', $data);

application/views/welcome.php

Hi, <strong><?php echo $username; ?></strong>! You are logged in now.

Answer 2

ok when user is logged in you need to store his or her data to session . when you verify user get his or her data and store that in session.

$data = array(
                   'username'  => 'johndoe',
                   'email'     => 'johndoe@some-site.com',
                   'logged_in' => TRUE
               );

$this->session->set_userdata('logged_info', $data );

and then you can get it any where like

$userdata = $this->session->userdata('logged_info');