PHP - MVC Architecture in Core PHP

Model-View-Controller (MVC) is a design pattern used to organize code in a structured way by separating concerns into three main components: Model, View, and Controller. In core PHP, implementing MVC means building this structure manually without relying on full frameworks, which helps developers understand the internal working of web applications more clearly.

Concept of MVC

MVC divides an application into three interconnected parts:

Model: Handles data and business logic
View: Handles presentation and user interface
Controller: Handles user input and acts as a bridge between Model and View

This separation improves code organization, maintainability, and scalability.

Components in Detail

Model

The Model represents the data layer of the application. It is responsible for interacting with the database, processing data, and enforcing business rules.

Example responsibilities:

Fetching records from the database
Inserting or updating data
Applying validation rules

Example:

class UserModel {
    public function getUserById($id) {
        // database query
        return "User data";
    }
}

The model does not deal with how data is displayed; it only manages the data itself.

View

The View is responsible for displaying data to the user. It contains HTML and minimal PHP code to render dynamic content.

Example:

<html>
<body>
    <h1><?php echo $user; ?></h1>
</body>
</html>

The view should not contain business logic. Its purpose is strictly presentation.

Controller

The Controller acts as an intermediary between the Model and the View. It receives user input, processes it using the Model, and passes the result to the View.

Example:

class UserController {
    public function show($id) {
        $model = new UserModel();
        $user = $model->getUserById($id);
        include 'views/user.php';
    }
}

The controller ensures that the correct data flows between the model and the view.

How MVC Works in Core PHP

A user makes a request (for example, visiting a URL).
The request is handled by a front controller (usually index.php).
The controller processes the request.
The controller calls the model to retrieve or manipulate data.
The model returns the data to the controller.
The controller passes the data to the view.
The view renders the final output to the user.

Folder Structure Example

A simple MVC structure in core PHP might look like this:

/project
    /models
    /views
    /controllers
    index.php

models contain data-related classes
views contain UI templates
controllers contain application logic

Routing in Core PHP MVC

Since core PHP does not provide built-in routing, developers often implement a basic routing mechanism.

Example:

$url = $_GET['url'] ?? 'home/index';
$urlParts = explode('/', $url);

$controllerName = ucfirst($urlParts[0]) . 'Controller';
$methodName = $urlParts[1] ?? 'index';

$controller = new $controllerName();
$controller->$methodName();

This allows dynamic mapping of URLs to controllers and methods.

Advantages of MVC

Clear separation of concerns
Easier maintenance and debugging
Reusable components
Better scalability for large applications
Improved collaboration among developers

Challenges in Core PHP MVC

Requires manual setup of structure and routing
No built-in security or validation features
More effort compared to using frameworks
Risk of poor implementation if not designed properly

When to Use MVC in Core PHP

MVC is suitable when:

Building medium to large applications
You need organized and maintainable code
You want to understand framework internals

For small scripts, MVC may be unnecessary overhead.

Conclusion

MVC architecture in core PHP provides a disciplined way to structure web applications by separating logic, data, and presentation. While it requires more manual effort compared to frameworks, it gives developers deeper control and understanding of application flow. By properly implementing MVC, applications become more modular, scalable, and easier to manage over time.