Working with Controllers

# CHAPTER 5

Working with Controllers #

1. Introduction #

2. Learning Objectives #

• Generate a Controller using the Artisan command-line tool.

• Route web traffic directly to Controller methods.

• Pass variables and arrays from a Controller into a View.

• Understand and utilize Resource Controllers for CRUD operations.

3. Beginner-Friendly Explanation #

4. Creating a Controller via Artisan #

Open your terminal and type:

php artisan make:controller UserController

*Magic!* Laravel instantly creates a beautifully formatted file at app/Http/Controllers/UserController.php.

5. Writing a Controller Method #

<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request;

class UserController extends Controller
{
    // Create a public method named 'show'
    public function show($id)
    {
        // 1. We will pretend we fetched this name from the database
        $user_name = "Alice";
        
        // 2. We return a view and PASS the data to it!
        // We use the compact() function to easily pass variables
        return view(&#039;profile', compact('user_name', 'id'));
    }
}

6. Connecting the Route to the Controller #

In routes/web.php:

<?php
use Illuminate\Support\Facades\Route;
// Don't forget to import the Controller at the top!
use App\Http\Controllers\UserController;

// When someone hits /user/5, trigger the 'show' method in UserController
Route::get(&#039;/user/{id}', [UserController::class, 'show']);

7. Reading Data in the View #

In resources/views/profile.blade.php:

<h1>User Profile Dashboard</h1>
<p>Viewing Profile ID: {{ $id }}</p>
<p>Welcome back, {{ $user_name }}!</p>

8. The Ultimate Shortcut: Resource Controllers #

Terminal Command:

php artisan make:controller PostController --resource

And in your web.php router, you can route all 7 URLs with ONE line of code:

Route::resource('posts', PostController::class);

*(This single line automatically handles GET /posts, POST /posts, GET /posts/{id}, DELETE /posts/{id}, etc!)*

9. Best Practices #

• Single Responsibility: If your UserController is handling user logins, user profiles, uploading user avatars, and sending user emails, it is too fat. Break it down. Create an AvatarController or an EmailController. Small controllers are easy to maintain.

10. Common Mistakes #

• Forgetting the use Statement in web.php: If you write Route::get('/', [UserController::class, 'index']); but forget to put use App\Http\Controllers\UserController; at the very top of the routing file, Laravel will crash with a "Class not found" error.

11. Exercises #

1. 1. Explain the "Hospital Analogy" to describe why we use Controllers instead of writing logic directly in the routing file.

12. Coding Challenges #

• Challenge: Use the terminal to create a ProductController. Write an index() method inside it that returns a view called products.index, and passes an array of three fake product names to that view.

13. MCQs with Answers #

14. Interview Questions #

• Q: How do you pass an array of database records from a Controller to a Blade View, and how does the concept of Separation of Concerns apply here?

• Q: What is a Resource Controller in Laravel, and what specific problem does the --resource flag solve for developers building CRUD applications?

15. FAQs #

16. Summary #

17. Next Chapter Recommendation #