add.php

<?php 
// File ini ada di application/views/add.php 
;?>
<h1>Add Post</h1>

<form action="" method="POST" id="postForm">
  <input type="text" name="title" />
  <textarea name="body"></textarea>
  <button type="submit">Simpan</button>
</form

<script type="text/javascript" src="http://code.jquery.com/jquery-1.10.1.min.js"></script>
<script type="text/javascript" src="http://jquery.bassistance.de/validate/jquery.validate.js"></script>
<script type="text/javascript">
  <?php
    // Cek Form validation menggunakan http://jquery.bassistance.de/validate/demo/
    // validate signup form on keyup and submit
    ?>
  $(document).ready(function(){
    $("#postForm").validate({
      rules: {
        title: "required",
        body: "required",
      },
      messages: {
        title: "Please enter your title",
        body: "Please enter your body"  
      }
    });
  });
</script>

edit.php

<?php 
// File ini ada di application/views/edit.php 
;?>
<h1>Add Post</h1>

<form action="" method="POST">
  <input type="text" name="title" value="<?php echo $post->title;?>" />
  <textarea name="body"><?php echo $post->body;?></textarea>

  <button type="submit">Simpan</button>
</form

index.php

<?php 
// File ini ada di application/views/index.php 
;?>
<h1>Post</h1>

<?php if ($posts):?>
  <?php foreach($posts as $post):?>
    <h1><?php echo $post->title;?></h1>
    <p><?php echo $post->body;?></p>
    <a href="/post/edit/<?php echo $post->id;?>">Edit</a>
    <a href="/post/delete/<?php echo $post->id;?>">Delete</a>
  <?php endforeach;?>
<?php else:?>
  Belum ada post
<?php endif;?>

Post.php

<?php

// File ini ada di application/controllers/post.php

class Post extends CI_Controller 
{
  public function index()
  {
    $this->load->model('post_model');
    $data['posts'] = $this->post_model->getAll();
    return $this->load->view('index', $data);
  }
  
  public function add()
  {
    if ($_POST){
      $this->load->library('form_validation');
      
      $this->form_validation->set_rules('title','Judul','required');
      $this->form_validation->set_rules('body','Isi post','required');
      
      if ($this->form_validation->run() == TRUE) {
        $this->db->insert('tb_posts', array(
          'title' => $this->input->post('title'),
          'body'  => $this->input->post('body')
        ));
      }
    }
    return $this->load->view('add');
  }
  
  public function edit($id)
  {
    $this->load->model('post_model');
    if ($_POST) {
      $this->load->library('form_validation');
      
      $this->form_validation->set_rules('title','Judul','required');
      $this->form_validation->set_rules('body','Isi post','required');
      
      if ($this->form_validation->run() == TRUE) {
        $this->db->update('tb_posts', array(
          'title' => $this->input->post('title'),
          'body'  => $this->input->post('body')
        ), array(
          'id'  => $id  
        ));
      }
    }
    
    $data['post'] = $this->post_model->getById($id);
    return $this->load->view('edit', $data);
  }
  
  public function delete($id)
  {
    $this->db->where('id', $id);
    return $this->db->delete('tb_posts');
  }
}

Post_Model.php

<?php

// File ini ada di application/controllers/post_model.php

class Post_Model extend CI_Model
{
  
  public function getAll()
  {
    $this->db->where('status', 1);
    $this->db->from('tb_posts');
    return $this->db->get()->result();
  }
  
  public function getById($id)
  {
    $this->db->where('status', 1);
    $this->db->where('id', $id);
    $this->db->from('tb_posts');
    return $this->db->get()->row();
  }

}