How to Create Multi level Nested category in Codeigniter

In this article, We will explain How to Create Multi level Nested category example in Codeigniter. you can use this example in Codeigniter Multilevel Menu.

Sometimes, we need to Multilevel Nested category in Codeigniter the create a comment system, multilevel menu, and e-commerce websites.

Here, we will use the recursion function, such as we are getting all the sub-categories through the main category, At that time we are using the recursion function.

so, you can follow the below steps.

How to Create Multi level Nested category in Codeigniter

Download and install Codeigniter

We are going to install Codeigniter 3, first, we will download a fresh Codeigniter 3 version and install it in our system. so you can follow below Link for Download CodeIgniter.

Create a Database in table

In this step, we have to create a table in the database, so we will create a database using the below code.

CREATE TABLE `categories` (
  `category_id` int(11) NOT NULL,
  `category_parent_id` varchar(255) NOT NULL,
  `category_name` varchar(255) NOT NULL,
  `category_created` datetime NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

--
-- Dumping data for table `categories`
--

INSERT INTO `categories` (`category_id`, `category_parent_id`, `category_name`, `category_created`) VALUES
(1, '0', 'asia', '2018-10-29 12:08:16'),
(2, '1', 'india', '2018-10-29 12:08:49'),
(3, '0', 'europe', '2018-10-29 12:10:16'),
(4, '0', 'africa', '2018-10-29 12:12:38'),
(5, '1', 'shri lanka', '2018-10-29 12:13:34'),
(6, '1', 'singapore', '2018-10-29 12:14:01'),
(7, '1', 'pakistan', '2018-10-29 12:14:41'),
(8, '1', 'bangladesh', '2018-10-29 12:15:08'),
(9, '4', 'Nigeria', '2018-10-29 12:15:40'),
(10, '4', 'Kenya', '2018-10-29 12:15:54'),
(11, '3', 'France', '2018-10-29 12:16:42'),
(12, '3', 'Germany', '2018-10-29 12:44:28'),
(13, '3', 'Iceland', '2018-10-29 12:17:26'),
(14, '2', 'gujarat', '2018-10-29 12:54:23'),
(15, '14', 'surat', '2018-10-29 01:03:14'),
(16, '15', 'katargam', '2018-12-08 05:55:44'),
(19, '12', 'berlin', '2018-12-08 06:06:18'),
(21, '11', 'paris', '2018-12-08 06:20:58'),
(22, '13', 'selfoss', '2018-12-08 06:22:50');

--
-- Indexes for dumped tables
--

--
-- Indexes for table `categories`
--
ALTER TABLE `categories`
  ADD PRIMARY KEY (`category_id`);

--
-- AUTO_INCREMENT for dumped tables
--

--
-- AUTO_INCREMENT for table `categories`
--
ALTER TABLE `categories`
  MODIFY `category_id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=23;
COMMIT;

Connect to Database

Go to the config folder and open database.php file some changes in this file like hostname, database username, database password, and database name.

$db['default'] = array(
	'dsn'	=> '',
	'hostname' => 'localhost',
	'username' => 'root',
	'password' => '',
	'database' => 'enter here database name',
	'dbdriver' => 'mysqli',
	'dbprefix' => '',
	'pconnect' => FALSE,
	'db_debug' => (ENVIRONMENT !== 'production'),
	'cache_on' => FALSE,
	'cachedir' => '',
	'char_set' => 'utf8',
	'dbcollat' => 'utf8_general_ci',
	'swap_pre' => '',
	'encrypt' => FALSE,
	'compress' => FALSE,
	'stricton' => FALSE,
	'failover' => array(),
	'save_queries' => TRUE
);

Create Controller

In this step, we will create a Category.php file in the “application/controller” directory and paste the below code in this controller.
application/controller/Category.php

<?php
defined('BASEPATH') OR exit('No direct script access allowed');


class Category extends CI_Controller {


    /**
    * Constructor of Controller
    *
    * @return Response
   */
    public function __construct() {
        parent::__construct();
        $this->load->model('Category_model');
    }

    public function categories(){

	    $data = $this->category_model->getcategory();
		echo "<pre>";
	    print_r($data);
		echo "</pre>";
    }
}

?>

Create a Model

In this step, we will create a Category_model.php file in the “application/models” directory and paste the below code in this model.
application/models/Category_model.php

<?php
if (!defined('BASEPATH'))
    exit('No direct script access allowed');
 
class Category_model extends CI_Model {
 
    public function getcategory(){

        $this->db->select('*');
        $this->db->from('categories');
        $this->db->where('category_parent_id', 0);

        $parent = $this->db->get();
        
        $categories = $parent->result();
        $i=0;
        foreach($categories as $main_cat){

            $categories[$i]->sub = $this->sub_category($main_cat->category_id);
            $i++;
        }
        return $categories;
    }

    public function sub_category($id){

        $this->db->select('*');
        $this->db->from('categories');
        $this->db->where('category_parent_id', $id);

        $child = $this->db->get();
        $categories = $child->result();
        $i=0;
        foreach($categories as $sub_cat){

            $categories[$i]->sub = $this->sub_category($sub_cat->category_id);
            $i++;
        }
        return $categories;       
    }
 
}
 
?>

We think would you like this article, so you can click on the “Show Demo” button and you can see this demo article.

Show Demo