FailOnUnknownFields

Description: Fails the form request validation if the request contains any fields not defined in the rules() method.

Namespace: Illuminate\Foundation\Http\Attributes\FailOnUnknownFields

Added in: Laravel 13.4

Usage

use Illuminate\Foundation\Http\Attributes\FailOnUnknownFields;
use Illuminate\Foundation\Http\FormRequest;

// Before:
No direct property equivalent — required custom validation logic

use Illuminate\Foundation\Http\Attributes\FailOnUnknownFields;
use Illuminate\Foundation\Http\FormRequest;

// After:
#[FailOnUnknownFields]
class StorePostRequest extends FormRequest
{
    public function rules(): array
    {
        return [
            'title' => ['required', 'string', 'max:255'],
            'body'  => ['required', 'string'],
        ];
    }
}

If the request contains an unexpected field like is_admin, validation will fail automatically.

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