Model/Controller: Call to a member function on a non-object

[eluser]convan23[/eluser]
I'm currently creating the part of my app that involves the user handling...login/logout, registration, account control, etc.

I'm working on the register account function, specifically the form validation, and I'm running into a problem where it checks to see if the email entered into the form already exists in the database.

Here's the code that relates to the problem:

Fatal error: Call to a member function on a non-object in /mnt/gs01/herd02/6813/domains/ci.epiphanyeyc.com/html/system/application/controllers/users.php on line 37

Which refers to:

Code:

function _chekemail($str){
    if($this->user_model->get_user('email',$str)){ return false; } else { return true; }
}

Which is in:
Controller:

Code:

function Users()
{
    parent::Controller();
    $this->load->library('encrypt');
    $this->load->model('user_model','',TRUE);
}

function register()
{
    $data['head_title'] = "Create an Account";
    
    // Validation:
    $this->load->library('validation');
            
    $rules['firstname']    = "trim|required|xss_clean";
    $rules['lastname']    = "trim|required|xss_clean";    
    $rules['email']        = "required|valid_email|_chekemail";    
    $rules['password']    = "required|matches[confirm]|min_length[6]";
    $rules['confirm']    = "required";
    
    $this->validation->set_message('required', '<p class="error"><strong>Required Field:</strong> Please enter your %s</p>');
    $this->validation->set_message('valid_email', '<p class="error"><strong>Invalid Email:</strong> Either your %s is invalid or it is already in use.</p>');
    $this->validation->set_message('min_length', '<p class="error"><strong>Invalid Length:</strong> Your %s must not exceed %s characters</p>');
    $this->validation->set_message('max_length', '<p class="error"><strong>Invalid Length:</strong> Your %s must be within %s characters</p>');
    $this->validation->set_message('matches', '<p class="error"><strong>Passwords Don\'t Match:</strong> Please make sure your passwords are the same in both fields</p>');
    
    $this->validation->set_rules($rules);
    
    $fields['firstname'] = 'first name';
    $fields['lastname'] = 'last name';
    $fields['homephone'] = 'home phone';
    $fields['mobilephone'] = 'mobile phone';
    $fields['streetaddress'] = 'street address';
    $fields['citystatezip'] = 'city, state. zip';
    $fields['email'] = 'email address';    
    $this->validation->set_fields($fields);
    // [END] Validation
    
    if ($this->validation->run() == false) { // If the form doesn't validate
        $this->template->load('template/default','/users/index', $data);
    } else { // If the form does validate, create the account and login to it
        $userdata = $this->input->post();
        $userdata['password'] = $this->encrypt->encode($userdata['password']);            
        
        if($this->user->add_user($userdata)) { // If add user sucessfull, login and redirect
            $this->_login('email',$userdata('email'),$this->input->post($password));
            $this->redirect('users/account');
        }
    }
}    
function _chekemail($str){
    if($this->user_model->get_user('email',$str)){ return false; } else { return true; }
}

Model:

Code:

<?php
    
class User_model extends Model {

    function User_model()
    {
        // Call the Model constructor
         parent::Model();
    }

    function get_user($key,$value)
    {
        $query = $this->db->query("SELECT * FROM users WHERE ".$key."=".$value);
        return $query->result();
    }

    function add_user()
    {
        foreach ($_POST as $key => $value) {
            $this->$key = $value;
        }

        if($this->db->insert('users', $this)) { return true; }
    }

    function edit_user()
    {
        foreach ($_POST as $key => $value) {
            $this->$key = $value;
        }

        $this->db->update('users', $this, array('id', $_POST['id']));
    }

}
?>

Also this is my first CI app so if I'm doing anything in a pointless or not-suggested-way way please let me know.