Codeigniter Interview Questions and Answers in 2025 (100+ Q&A)

Codeigniter

Ques:- Explain application flow chart in codeigniter?

Asked In :-

Right Answer:
In CodeIgniter, the application flow chart typically follows these steps:

1. **Index.php**: The entry point of the application.
2. **Bootstrap**: Loads the framework and initializes the application.
3. **Routing**: The URI is parsed to determine the controller and method to call.
4. **Controller**: The specified controller is instantiated.
5. **Model**: If needed, the controller interacts with the model to retrieve or manipulate data.
6. **View**: The controller loads the appropriate view to display the output.
7. **Output**: The final output is sent to the browser.

This flow ensures a structured approach to handling requests and responses in a CodeIgniter application.

Codeigniter

Ques:- Can you extend native libraries in codeigniter?

Asked In :-

Right Answer:
Yes, you can extend native libraries in CodeIgniter by creating a new library that extends the existing one.

Codeigniter

Ques:- How can you create a library in codeigniter?

Asked In :-

Right Answer:
To create a library in CodeIgniter, follow these steps:

1. Create a new PHP file in the `application/libraries` directory. Name it according to your library, e.g., `MyLibrary.php`.
2. Define a class in that file with the same name as the file, and ensure it extends the `CI_Controller` or `CI_Model` class if needed.
3. Use the `__construct()` method to initialize any necessary properties.
4. Add your library methods within the class.
5. Load the library in your controller using `$this->load->library('MyLibrary');`.

Example:

```php
// File: application/libraries/MyLibrary.php
defined('BASEPATH') OR exit('No direct script access allowed');

class MyLibrary {
public function __construct() {
// Initialization code here
}

public function myMethod() {
// Your method code here
}
}
```

In your controller:

```php
$this->load->

Codeigniter

Ques:- How can you extend class in codeigniter?

Asked In :-

Right Answer:
In CodeIgniter, you can extend a class by creating a new file in the `application/core` directory and naming it with the prefix `MY_`. For example, to extend the `Controller` class, you would create a file named `MY_Controller.php` and define your class like this:

```php
class MY_Controller extends CI_Controller {
// Your custom code here
}
```

Make sure to load your extended class in your controllers by extending `MY_Controller` instead of `CI_Controller`.

Codeigniter

Ques:- How to unset session in codeigniter?

Asked In :- briskminds software solutions pvt. ltd.,

Right Answer:
To unset a session in CodeIgniter, you can use the following code:

```php
$this->session->unset_userdata('session_key');
```

To destroy all session data, use:

```php
$this->session->sess_destroy();
```

Codeigniter

Ques:- Explain views in codeigniter?

Asked In :-

Right Answer:
In CodeIgniter, views are files that contain the HTML and PHP code used to present data to the user. They are responsible for the user interface and are typically stored in the `application/views` directory. Views are loaded by controllers and can receive data from them to display dynamic content.

Codeigniter

Ques:- Explain codeigniter file structure?

Asked In :-

Right Answer:
CodeIgniter's file structure consists of the following main directories:

1. **application/**: Contains the application code, including controllers, models, views, and configuration files.
- **config/**: Configuration files for the application.
- **controllers/**: Contains controller classes.
- **models/**: Contains model classes.
- **views/**: Contains view files.
- **libraries/**: Custom libraries.
- **helpers/**: Helper functions.
- **hooks/**: Hook files for extending the framework.
- **language/**: Language files for localization.
- **migrations/**: Database migration files.

2. **system/**: Contains the core CodeIgniter framework files.

3. **user_guide/**: Documentation for CodeIgniter (not used in production).

4. **index.php**: The front controller that initializes the framework.

5. **.htaccess**: Configuration file for URL rewriting (optional).

6. **assets/**

Codeigniter

Ques:- What is the default method name in codeigniter?

Asked In :-

Right Answer:
The default method name in CodeIgniter is `index`.

Codeigniter

Ques:- What is helper in codeigniter? How can you load a helper file?

Asked In :-

Right Answer:
A helper in CodeIgniter is a file that contains a set of functions that assist in performing common tasks, such as formatting data or working with URLs. You can load a helper file using the following code in your controller:

```php
$this->load->helper('helper_name');
```

Replace `helper_name` with the name of the helper file you want to load (without the `.php` extension).

Codeigniter

Ques:- How to access config variable in codeigniter?

Asked In :-

Right Answer:
You can access a config variable in CodeIgniter using the `get_config_item()` function or by using the `$this->config` object. For example:

```php
$value = $this->config->item('config_item_name');
```

or

```php
$value = get_config_item('config_item_name');
```

Codeigniter

Ques:- What is basic codeigniter url structure?

Asked In :-

Right Answer:
The basic CodeIgniter URL structure is:

`http://your-domain/index.php/controller/method/parameter`

Where:
- `your-domain` is your website's domain.
- `index.php` is the front controller.
- `controller` is the name of the controller class.
- `method` is the function within the controller.
- `parameter` is an optional parameter passed to the method.

Codeigniter

Ques:- How can you connect models to a database manually?

Asked In :-

Right Answer:
In CodeIgniter, you can connect models to a database manually by loading the database library in the model's constructor. Here’s how you can do it:

```php
class YourModel extends CI_Model {
public function __construct() {
parent::__construct();
$this->load->database(); // Load the database
}
}
```

Codeigniter

Ques:- Explain remapping method calls in codeigniter?

Asked In :-

Right Answer:
In CodeIgniter, remapping method calls can be done using the `_remap()` method in a controller. This method allows you to intercept all requests to the controller and redirect them to different methods based on custom logic. You define the `_remap()` method in your controller, and within it, you can call other methods or perform actions before returning a response. For example:

```php
class MyController extends CI_Controller {
public function _remap($method, $params = array()) {
if (method_exists($this, $method)) {
return call_user_func_array([$this, $method], $params);
} else {
// Handle the case where the method does not exist
show_404();
}
}
}
```

Codeigniter

Ques:- Why is there a need to configure the url routes?

Asked In :-

Right Answer:
Configuring URL routes in CodeIgniter is necessary to create clean, user-friendly URLs, improve SEO, and map specific URLs to the appropriate controllers and methods, allowing for better organization and management of the application's routing logic.

Codeigniter

Ques:- List out different types of hook point in codeigniter?

Asked In :-

Right Answer:
The different types of hook points in CodeIgniter are:

1. Pre-system
2. Pre-controller
3. Post-controller constructor
4. Post-controller
5. Pre-render
6. Post-system

Codeigniter

Ques:- What is stable version of codeigniter?

Asked In :-

Right Answer:
The stable version of CodeIgniter as of October 2023 is CodeIgniter 4.4.0.

Codeigniter

Ques:- Who developed codeigniter?

Asked In :-

Right Answer:
CodeIgniter was developed by EllisLab.

Codeigniter

Ques:- What are the features of codeigniter? Open source framework?

Asked In :-

Right Answer:
CodeIgniter is an open-source PHP framework that offers several features, including:

1. **Lightweight**: Minimal footprint and fast performance.
2. **MVC Architecture**: Follows the Model-View-Controller design pattern.
3. **Built-in Libraries**: Provides numerous libraries for common tasks like database interaction, session management, and form validation.
4. **Easy Configuration**: Simple setup and configuration process.
5. **Security Features**: Includes features like XSS filtering and SQL injection protection.
6. **Extensible**: Allows developers to create custom libraries and helpers.
7. **Active Record Database Support**: Simplifies database queries with an easy-to-use syntax.
8. **Community Support**: Strong community and extensive documentation available.
9. **Routing**: Flexible routing system for URL management.
10. **Error Handling**: Built-in error handling and logging capabilities.

Codeigniter

Ques:- How you can prevent codeigniter from csrf?

Asked In :-

Right Answer:
To prevent CSRF in CodeIgniter, you can enable CSRF protection by setting the following in the `application/config/config.php` file:

```php
$config['csrf_protection'] = TRUE;
```

Additionally, ensure that you include the CSRF token in your forms using:

```php
<input type="hidden" name="<?= $this->security->get_csrf_token_name(); ?>" value="<?= $this->security->get_csrf_hash(); ?>" />
```

Codeigniter

Ques:- What are hooks in codeigniter?

Asked In :-

Right Answer:
Hooks in CodeIgniter are a way to extend the framework's functionality without modifying the core files. They allow you to execute custom code at specific points during the execution of the application, such as before or after the controller is called, or before the output is sent to the browser.

The CodeIgniter category on takluu.com is tailored for web developers preparing for interviews and jobs requiring knowledge of the CodeIgniter PHP framework. Known for its lightweight and fast performance, CodeIgniter is widely used to build dynamic web applications with the Model-View-Controller (MVC) architecture.

This section covers important topics such as CodeIgniter installation, MVC framework basics, routing, controllers, models, views, database interaction, form validation, and session management. You’ll also find questions related to security features, error handling, libraries, and helpers that are critical in real-world applications.

Interviewers often test candidates on practical scenarios such as:

“How do you create and manage routes in CodeIgniter?”
“Explain the role of controllers and models.”
“How does CodeIgniter handle security and data validation?”

Our content simplifies complex framework concepts through clear explanations, code snippets, and example projects. Whether you are a fresher or an experienced developer, this category will help you strengthen your foundation and prepare effectively for technical rounds.

At Takluu, we keep the CodeIgniter content updated with the latest version features and best practices to ensure you stay ahead in your career and interview preparation.

Questions in: Codeigniter

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