public function register($name,$email,$password) {
            $data = array(
                'name' => $name,
                'email' => $email,
                'password' => $password
            );
            $this->db->insert("users",$data);
            return true;
}

public function verifyUser() {
        $emailAdrees = $this->input->post('email');
        $password = $this->input->post('password');

        $isExistingUser = $this->AuthenticationModel->authecticateUser($emailAdrees, $password);
        if ($isExistingUser === TRUE) {
            $data['messages'] = '';
            $data['success'] = true;
        } else {
            $data['messages'] = 'Unable to login';
            $data['success'] = false;
        }

        echo json_encode($data);
}

var registerUserModel = Backbone.Model.extend({
                urlRoot: "http://localhost/Sample/index.php/MainController/addUser",
                defaults: {
                    name: '',
                    email: '',
                    password: ''
                }
            });



            var newRegisteredUser = function (name, email, password) {
                var newUser = new registerUserModel();
                var newUserDetails = {
                    name: name,
                    email: email,
                    password: password
                };
                console.log(newUserDetails.name);



                newUser.save(newUserDetails,{

                        success: function () {
                        alert("success");


                    },
                    error: function () {

                        console.log("fail") //Always error
                    }

                });
            };