global variable in laravel

SET configuration variables at runtime:
class AppServiceProvider extends ServiceProvider
{
    public function boot()
    {
        View::share('key', 'value');
        Schema::defaultStringLength(191);
        $company=DB::table('company')->where('id',1)->first();
        config(['yourconfig.company' => $company]);
    }
}

USE:
config('yourconfig.company');

// AppServiceProvider

public function boot()
{
    View::share('globalVarName', 'Global Var Value');
}

class TestController extends Controller
{
    private $x;

    public function index()
    {
        $this->x ='22';
    }

    public function send_message()
    {
        echo $this->x;
    }
}