Logout Function in PHP

 

 This is for Codeigniter :-

function logout()
{
    $user_data = $this->session->all_userdata();
        foreach ($user_data as $key => $value) {
                $this->session->unset_userdata($key);
        }
    $this->session->sess_destroy();

/////Here you have to write redirect url example : redirect("login"); 

 }

  This is for Core PHP:- 

function logout()
{

session_start();

 $_SESSION['email']=""; /// Here we are showing example to set empty to session key's value

 session_destroy();

/////Here you have to write redirect url example : header("Location: login.php");  

}