Dingo\Api\Dispatcher::setDefaultFormat PHP Method

    public function setDefaultFormat($format)
    {
        $this->defaultFormat = $format;
    }

 /**
  * Register the internal dispatcher.
  *
  * @return void
  */
 public function registerDispatcher()
 {
     $this->app->singleton('api.dispatcher', function ($app) {
         $dispatcher = new Dispatcher($app, $app['files'], $app['api.router'], $app['api.auth']);
         $config = $app['config']['api'];
         $dispatcher->setVendor($config['vendor']);
         $dispatcher->setPrefix($config['prefix']);
         $dispatcher->setDefaultVersion($config['version']);
         $dispatcher->setDefaultDomain($config['domain']);
         $dispatcher->setDefaultFormat($config['defaultFormat']);
         return $dispatcher;
     });
 }