How to create a form using block module in drupal 8?

Question

I want build a form using a block module in Drupal 8. I am aware of building the forms in Drupal 7 but the same seems to be different in Drupal 8.

Answer 1

Here is a detailed summary of how to go about this:-

https://www.sitepoint.com/building-drupal-8-module-blocks-forms/

Following the above guide, you would add the completed form to the block build function, e.g.

class DemoBlock extends BlockBase {

  /**
   * {@inheritdoc}
   */
  public function build() {    
    $form = \Drupal::formBuilder()->getForm('Drupal\demo\Form\DemoForm');
    return $form;
  }

}

Some more useful docs if you are new to Drupal 8 or need to dust off your knowledge:

https://www.drupal.org/docs/8/creating-custom-modules

https://www.drupal.org/docs/8/api/block-api

https://www.drupal.org/docs/8/api/form-api