无法在codeigniter中调用函数

Question

I am new in CodeIgniter now I am creating a site. an Admin can view all records after login but unfortunately, the target URL shows 404 Page Not Found. I am using temple(header n footer) for a menu. here is my header.php

<div class="collapse navbar-collapse" id="navbarColor01">
      <ul class="navbar-nav mr-auto" >
<?php if(!$this->session->userdata('logged_in')) : ?>
        <li class="nav-item"><a class="nav-link" href="<?php echo base_url(); ?>users/login">Login</a></li>
        <li class="nav-item"><a class="nav-link" href="<?php echo base_url(); ?>users/register">Register</a></li>
      <?php endif; ?>
      <?php if($this->session->userdata('logged_in')) : ?>
      <li class="nav-item"><a class="nav-link" href="<?php echo base_url(); ?>posts">List Item</a></li>
        <li class="nav-item"><a class="nav-link" href="<?php echo base_url(); ?>posts/create">Create Post</a></li>
        <li class="nav-item"><a class="nav-link" href="<?php echo base_url(); ?>users/logout">Logout</a></li>
        <li class="nav-item"><a class="nav-link" href="<?php echo base_url(); ?>admin">Admin</a></li>
      <?php endif; ?>
      </ul>
    </div>

When I click the admin menu then it should be goto Admin Controller and call index function for cofirmation i put echo and die but it shows 404 error. here is my Admin Controller

<?php
class Admin extends CI_Controller{
    public function index(){    
        echo "Reach here"; die;
        if (!$this->session->userdata('logged_in')) {
            redirect('users/login');
        }
?>

Thanks in advance for assistance.

Answer 1

Put your admin link like this :

as Admin is not your default controller and you not set your route for admin

Put your admin link like this

<li class="nav-item">
  <a class="nav-link" href="<?php echo base_url('admin/index'); ?>">Admin</a> 
</li>

but if you want to do like this :

<li class="nav-item">
      <a class="nav-link" href="<?php echo base_url('admin'); ?>">Admin</a> 
</li>

then set route.php like this :

$route['admin'] = 'admin/index';

And controller :

<?php
class Admin extends CI_Controller{
    public function index(){    
        echo "Reach here"; die;
        if (!$this->session->userdata('logged_in')) {
            redirect('users/login');
        }
?>