An uncaught Exception was encountered: Call to undefined method codeigniter

Question

Please help me. I've tried to solve it, but what is the problem in my code? This is my first time to encounter this error. I really need help, please.

This is the error I'm getting:

Message: Call to undefined method M_data::cek_login() in C:\xampp\htdocs\perpustakaan\application\controllers\Login.php Line Number: 32

here is my controllers :

<?php 
defined('BASEPATH') or exit('No direct script access allowed');
class Login extends CI_Controller
{
    function __construct()
    {
        parent::__construct();
    }  
    public function index()
    {
        $this->load->view('v_login');
    }
   
    public function login_aksi()
    {
        $username = $this->input->post('username');
        $password = $this->input->post('password');
        $sebagai = $this->input->post('sebagai');

        $this->form_validation->set_rules('username', 'Username', 'required');
        $this->form_validation->set_rules('password', 'Password', 'required');

        if ($this->form_validation->run() != false) {
            $where = array(
                'username' => $username,
                'password' => md5($password)
            );

            if ($sebagai == "admin") {
                $cek = $this->m_data->cek_login('admin', $where)->num_rows();
                $data = $this->m_data->cek_login('admin', $where)->row();
                if ($cek > 0) {
                    $data_session = array(
                        'id' => $data->id,
                        'username' => $data->username,
                        'status' => 'admin_login'
                    );
                    $this->session->set_userdata($data_session);
                    redirect(base_url() . 'admin');
                } else {
                    redirect(base_url() . 'login?alert=gagal');
                }
            } else if ($sebagai == "petugas") {
                $cek = $this->m_data->cek_login('petugas', $where)->num_rows();
                $data = $this->m_data->cek_login('petugas', $where)->row();
                if ($cek > 0) {
                    $data_session = array(
                        'id' => $data->id,
                        'nama' => $data->nama,
                        'username' => $data->username,
                        'status' => 'petugas_login'
                    );
                    $this->session->set_userdata($data_session);
                    redirect(base_url() . 'petugas');
                } else {
                    redirect(base_url() . 'login?alert=gagal');
                }
            }
        } else {
            $this->load->view('v_login');
        }
    }
}

My Models :

<?php

class M_data extends CI_Model
{

    function get_data($table)
    {
        return $this->db->get($table);
    }

    function insert_data($data, $table)
    {
        $this->db->insert($table, $data);
    }

    function edit_data($where, $table)
    {
        return $this->db->get_where($table, $where);
    }

    function update_data($where, $data, $table)
    {
        $this->db->where($where);
        $this->db->update($table, $data);
    }

    function delete_data($where, $table)
    {
        $this->db->delete($table, $where);
    }
}

Answer 1

it's because you don't have any function called cek_login() inside M_data.

you should define it like :

function cek_login($table, $where)
{
    //put your script here
}