CodeIgniter Interview Guide: From Basics to Advanced Concepts
Table of Contents
Basic CodeIgniter Interview Questions:
1. What is CodeIgniter?
CodeIgniter is a lightweight and powerful PHP web application framework used to build dynamic websites. It follows the MVC (Model-View-Controller) architecture for structured development.
2. Explain the MVC architecture in CodeIgniter.
In CodeIgniter, MVC separates the application logic into three components: Models (handle data), Views (display output), and Controllers (manage user input and interactions).
3. How do you load a model in CodeIgniter?
$this->load->model('ModelName');
4. What is a CodeIgniter controller?
A controller in CodeIgniter is a class file that manages the flow of the application. It receives input, processes it, and returns the appropriate output.
5. How can you pass data from a controller to a view in CodeIgniter?
By using the $this->load->view() function with an optional second parameter, an array of data.
$data = array('key' => 'value');
$this->load->view('view_name', $data);Advanced CodeIgniter Interview Questions:
6. Explain CodeIgniter routing.
Routing in CodeIgniter refers to the process of determining how a URI request should be mapped to a specific controller method.
7. What is CodeIgniter helper?
A CodeIgniter helper is a collection of utility functions that assist in performing common tasks, such as working with URLs, forms, and arrays.
8. How to enable and use CodeIgniter database caching?
Enable caching in the database configuration file (config/database.php).
$db['default']['cache_on'] = TRUE; $db['default']['cachedir'] = APPPATH . 'cache';
9. What is the purpose of the CodeIgniter URI class?
The URI class in CodeIgniter provides methods to retrieve information from the URI, such as segments and query strings.
10. Explain CodeIgniter’s form validation.
CodeIgniter’s form validation class helps validate form input data before processing it. It provides a set of rules and functions for common validation tasks.
11. How to use sessions in CodeIgniter?
CodeIgniter uses the session library to handle sessions.
$this->session->set_userdata('key', 'value');12. What is CodeIgniter encryption, and how is it used?
CodeIgniter provides an encryption library for secure data handling. You can use it to encrypt and decrypt sensitive information.
13. How to create a custom helper in CodeIgniter?
Create a PHP file in the application/helpers directory and define your functions. Load the helper using $this->load->helper('helper_name');.
14. Explain CodeIgniter hooks.
Hooks in CodeIgniter allow you to execute custom code at specific points during the request lifecycle. They provide a way to extend the framework’s functionality.
15. What is CodeIgniter’s CSRF protection, and why is it important?
CSRF (Cross-Site Request Forgery) protection in CodeIgniter helps prevent unauthorized form submissions. It generates and verifies unique tokens for each form.
Please find below another important question and its corresponding answer.