Gremoire

Building a PHP Web Application with CodeIgniter ​

CodeIgniter is a powerful PHP framework known for its simplicity and speed. It follows the Model-View-Controller (MVC) architecture, making it easy to organize and maintain your codebase. In this article, we'll walk through the process of creating a simple web application using CodeIgniter.

Step 1: Setting Up CodeIgniter ​

  1. Download CodeIgniter: Visit the CodeIgniter website and download the latest version of CodeIgniter.
  2. Extract Files: Extract the downloaded file to your desired directory.
  3. Configuration: Adjust configuration settings in application/config/config.php if necessary.
  4. Test Installation: Visit your project's URL to ensure CodeIgniter is set up correctly.

or

  1. create project using composer:
sh
composer create-project codeigniter4/appstarter projectName

Step 2: Creating a Controller ​

  1. Create a Controller File: Inside the application/controllers directory, create a new PHP file, e.g., Welcome.php.
  2. Define Class: Define a class with the same name as the file, extending CI_Controller.
  3. Create Methods: Define methods within the class to handle different requests.
php
<?php
class Welcome extends CI_Controller {
    public function index() {
        $this->load->view('welcome_message');
    }
}

Step 3: Creating Views ​

  1. Create View Files: Inside the application/views directory, create PHP files for your views, e.g., welcome_message.php.
  2. Write HTML: Write HTML and PHP code in the view files to display the content.
php
<!DOCTYPE html>
<html>
<head>
    <title>Welcome to My Website</title>
</head>
<body>
    <h1>Welcome to My Website</h1>
    <p>This is a simple CodeIgniter MVC application.</p>
</body>
</html>

Step 4: Creating a Route ​

  1. Define Routes: Open application/config/routes.php.
  2. Set Default Route: Set a default route to your controller.
php
$route['default_controller'] = 'welcome';

Step 5: Testing Your Application ​

Visit your project's URL in a web browser. You should see the content from your view file being displayed.

Step 6: Expand and Refine ​

Continue expanding your application by adding more controllers, views, and models as needed. Configure database settings in application/config/database.php and use models to interact with the database.