MVC architecture overview in PHP - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this PHP MVC code snippet?

Consider a simple MVC setup where the Controller calls the Model to get data and then passes it to the View. What will be printed?

PHP

<?php
class Model {
    public function getData() {
        return 'Hello from Model';
    }
}

class View {
    public function render($data) {
        echo $data;
    }
}

class Controller {
    private $model;
    private $view;

    public function __construct() {
        $this->model = new Model();
        $this->view = new View();
    }

    public function show() {
        $data = $this->model->getData();
        $this->view->render($data);
    }
}

$controller = new Controller();
$controller->show();

A No output

B Hello from Model

C Fatal error: Call to undefined method

D Hello from View

💡 Hint

Think about which class returns the string and which class prints it.

The Model's getData() method returns the string 'Hello from Model'. The Controller calls this method and passes the result to the View's render() method, which prints it.

🧠 Conceptual

intermediate

Which MVC component is responsible for handling user input?

In the MVC architecture, which component typically handles user input and decides what to do next?

A Model

B View

C Database

D Controller

💡 Hint

Think about who acts like the traffic cop directing traffic.

The Controller handles user input, processes it, and decides which Model or View to use next.

🔧 Debug

advanced

Why does this MVC PHP code cause an error?

Look at this PHP MVC code. Why does it cause a fatal error?

PHP

<?php
class Model {
    public function getData() {
        return 'Data';
    }
}

class View {
    public function render() {
        echo $data;
    }
}

class Controller {
    private $model;
    private $view;

    public function __construct() {
        $this->model = new Model();
        $this->view = new View();
    }

    public function show() {
        $data = $this->model->getData();
        $this->view->render();
    }
}

$controller = new Controller();
$controller->show();

A Controller constructor missing parameters

B Model class missing getData method

C Undefined variable $data in View::render()

D View class cannot echo strings

💡 Hint

Check the variable usage inside the View's render method.

The View's render() method tries to echo $data, but $data is not defined inside that method's scope, causing a fatal error.

📝 Syntax

advanced

Which option fixes the syntax error in this MVC PHP snippet?

Find the option that fixes the syntax error in this PHP MVC code:

class Controller {
    public function show() {
        $data = $this->model->getData()
        $this->view->render($data);
    }
}

A Add a semicolon after getData() call

B Change getData() to getData;

C Remove parentheses from getData

D Add curly braces around getData()

💡 Hint

Look carefully at the end of the line calling getData().

PHP requires a semicolon at the end of each statement. Missing it causes a syntax error.

🚀 Application

expert

How many items are in the array passed from Model to View?

The Model returns an array of users to the Controller, which passes it to the View. How many users will the View receive?

PHP

<?php
class Model {
    public function getUsers() {
        return [
            ['name' => 'Alice', 'age' => 30],
            ['name' => 'Bob', 'age' => 25],
            ['name' => 'Charlie', 'age' => 35]
        ];
    }
}

class View {
    public function render($users) {
        echo count($users);
    }
}

class Controller {
    private $model;
    private $view;

    public function __construct() {
        $this->model = new Model();
        $this->view = new View();
    }

    public function showUsers() {
        $users = $this->model->getUsers();
        $this->view->render($users);
    }
}

$controller = new Controller();
$controller->showUsers();

A 3

B 2

C 1

D 0

💡 Hint

Count the number of user arrays inside the returned array.

The Model returns an array with 3 user arrays. The View counts and prints 3.