localhost/app

http://localhost/app

The localhost/app path is commonly used for web application development, serving as the root directory for full-stack applications, single-page apps (SPAs), and custom web projects during local development.

→ Open localhost/app

Application Directory Structure

htdocs/app/
├── public/              # Public web root
│   ├── index.php
│   ├── css/
│   ├── js/
│   └── images/
├── src/                 # Application source code
│   ├── controllers/
│   ├── models/
│   ├── views/
│   └── config/
├── vendor/              # Composer dependencies
├── node_modules/        # NPM dependencies
├── composer.json
├── package.json
└── .htaccess
    

Create Basic PHP Application

<?php
// app/public/index.php
session_start();

// Simple routing
$request = $_SERVER['REQUEST_URI'];
$request = str_replace('/app', '', $request);

switch ($request) {
    case '/':
        require __DIR__ . '/../src/views/home.php';
        break;
    case '/about':
        require __DIR__ . '/../src/views/about.php';
        break;
    case '/contact':
        require __DIR__ . '/../src/views/contact.php';
        break;
    default:
        http_response_code(404);
        require __DIR__ . '/../src/views/404.php';
        break;
}
?>
    

MVC Application Structure

// src/controllers/UserController.php
class UserController {
    private $userModel;
    
    public function __construct() {
        require_once __DIR__ . '/../models/User.php';
        $this->userModel = new User();
    }
    
    public function index() {
        $users = $this->userModel->getAll();
        require __DIR__ . '/../views/users/index.php';
    }
    
    public function show($id) {
        $user = $this->userModel->find($id);
        require __DIR__ . '/../views/users/show.php';
    }
}

// src/models/User.php
class User {
    private $db;
    
    public function __construct() {
        $this->db = new PDO('mysql:host=localhost;dbname=myapp', 'root', '');
    }
    
    public function getAll() {
        $stmt = $this->db->query('SELECT * FROM users');
        return $stmt->fetchAll(PDO::FETCH_ASSOC);
    }
    
    public function find($id) {
        $stmt = $this->db->prepare('SELECT * FROM users WHERE id = ?');
        $stmt->execute([$id]);
        return $stmt->fetch(PDO::FETCH_ASSOC);
    }
}

// src/views/users/index.php



    Users


    All Users
    
        <?php foreach ($users as $user): ?>
            <?php echo htmlspecialchars($user['name']); ?>

        <?php endforeach; ?>
    


    

React Single Page Application

# Create React app in app directory
cd C:\xampp\htdocs
npx create-react-app app

# Start development server
cd app
npm start

# Builds to: http://localhost:3000
# For production: npm run build
# Deploy build/ folder to htdocs/app/

# Access production build at: http://localhost/app
    

Fix "localhost/app Not Found"

Create App Directory

# Windows XAMPP
cd C:\xampp\htdocs
mkdir app
cd app
echo "<?php phpinfo(); ?>" > index.php

# Linux
cd /var/www/html
sudo mkdir app
sudo nano app/index.php

# Set permissions
sudo chown -R www-data:www-data app
sudo chmod -R 755 app
    

Laravel Application Setup

# Install Laravel in app directory
cd C:\xampp\htdocs
composer create-project laravel/laravel app

# Start development server
cd app
php artisan serve

# Access at: http://localhost:8000

# Or configure virtual host for http://localhost/app
    

Organization Tip: Use the /app directory as your main application folder. Keep public assets in public/, source code in src/, and configuration in config/ for better organization and security.

Frequently Asked Questions

What is localhost/app used for?

It's a common path for web application development, serving as the root directory for your application code, assets, and configuration during local development.

How do I access my app at localhost/app?

Create an "app" folder in htdocs (XAMPP) or www (WAMP), add an index.php or index.html file, ensure Apache is running, then visit http://localhost/app in your browser.

Can I run multiple apps on localhost?

Yes, create separate folders like /app1, /app2, or use virtual hosts to assign different domains like app1.local, app2.local pointing to different directories.

Related URLs and Resources

localhost/api - API endpoints
localhost/admin - Admin panel
localhost/dev - Development path
localhost/demo - Demo applications