Laravel Cheat Sheet - Form

Forms

CSRF Protection

In Laravel 5.7 you create form by simple HTML

<form method="POST" action="{{ route('posts.store') }}">

</form>

CSRF protection is enabled by default, so you need to include a CSRF token with each form sent

Token can be included by adding a @csrf directive inside the <form> tag. It would generate an <input> of type hidden with the token as value

<form method="POST" action="{{ route('posts.store') }}">
    @csrf
</form>

The token is then verified inside Laravel using the VerifyCsrfToken middleware.

Middleware

Middleware is a mechanism that filter requests going through your application.

Simply put - each middleware is a chunk of code that runs BEFORE or AFTER the request is handled by Controller Action or a Closure.

Below is an example flow of the request going through your application:

An example AFTER middleware from Laravel Docs

namespace App\Http\Middleware;

use Closure;

class AfterMiddleware
{
    public function handle($request, Closure $next)
    {
        // Calling $next with $request parameter
        $response = $next($request);

        // Do something here after the request is handled by Controller/Closure

        return $response;
    }
}

An example BEFORE middleware

namespace App\Http\Middleware;

use Closure;

class BeforeMiddleware
{
    public function handle($request, Closure $next)
    {
        // Do something here before the request is handled by Controller/Closure...

        // Calling $next with $request parameter
        return $next($request);
    }
}

Middleware should call the passed Closure $next with the $request parameter to allow further processing, or throw an Exception or do a redirect to stop further processing of the Request.

Middleware examples:

• Authentication (veryfying if user is authenticated)
• CSRF protection
• CORS middleware

Request

Obtaining data sent with request

class PostController extends Controller
{
    public function store(Request $request)
    {
        $title = $request->input('title');
    }
}

Reading all input as an array

$input = $request->all();

Reading an individual value with default provided

$name = $request->input('title', 'Draft post');

Retrieving all of the input values as an array

$input = $request->input();

The input() method can read data regardless of the HTTP verb used (works for GET query parameters or input fields sent through <form> with POST method)

Veryfing if input value is present

if ($request->has('title')) {
    // Do something with title
}

Redirects

Redirect to a URL

return redirect('/posts');

Redirect to a route with "flashed input"

return redirect('/posts/create')->withInput();

Redirect to last URL with "flashed input"

return back()->withInput();

Redirect to a named route

return redirect()->route('posts.index');

Redirect with flash message

return redirect()->route('posts')->with('status', 'New post created!');

Flashing input

Sometimes you need to repopulate the form with the old input, eg. when validation failed and you don't want the user to re-type all the fields.

You can do

$request->flash();

Or the above example (flash input and redirect)

return redirect('form')->withInput();

Source: Laravel Cheat Sheet