Identify submit button in webform

Question

I am trying to add additional submit buttons to the webform to navigate between different steps. I have added button like below:

function mymodule_form_alter(&$form, \Drupal\Core\Form\FormStateInterface $form_state, $form_id) {

  if($form_id == 'mywebform_id') {

    $form['actions']['submit_button_step_1'] = array(
      '#type' => 'submit',
      '#value' => t('Go to Step 1'),
      '#submit' => array('custom_navigation'),
    );

    $form['actions']['submit_button_step_2'] = array(
      '#type' => 'submit',
      '#value' => t('Go to Step 2'),
      '#submit' => array('custom_navigation'),
    );
  }
}

function custom_navigation(&$form, \Drupal\Core\Form\FormStateInterface $form_state) {

  $value = $form_state->getValues();
  //echo '<pre>';print_r($form['actions']);echo '</pre>';exit;
}

But, I'm using same custom submit handler both the custom buttons. How I identify which button has clicked by user? And based on user click I need to redirect user to corresponding wizard page.

Answer 1

Below codes work for two submit buttons given at webform for identify which button is click.

function modulename_form_submit(&$form, FormStateInterface $form_state) {

  $myurl = FALSE;
  $triggerElement = $form_state->getTriggeringElement();

  if (isset($triggerElement['#id']) && $triggerElement['#id'] == 'COMPARE BUTTON ID') {
    $myurl = Url::fromUri('internal:/SETYOURFIRSTACTIONPATH');
  }

  if (isset($triggerElement['#id']) && $triggerElement['#id'] == 'COMPARE ANOTHER BUTTON ID') {
    $myurl = Url::fromUri('internal:SETYOURSECONDACTIONPATH');
  }

  if ($myurl) {
    $form_state->setRedirectUrl($myurl);
  }
}

Answer 2

function mymodule_form_alter(&$form, \Drupal\Core\Form\FormStateInterface $form_state, $form_id) {
  if ($form_id == 'mywebform_id') {
    $form['actions']['submit_button_step_1'] = array(
      '#type' => 'submit',
      '#name' => 'step_1',
      '#value' => t('Go to Step 1'),
      '#submit' => array('custom_navigation'),
    );
    $form['actions']['submit_button_step_2'] = array(
      '#type' => 'submit',
      '#name' => 'step_2',
      '#value' => t('Go to Step 2'),
      '#submit' => array('custom_navigation'),
    );
  }
}

function custom_navigation(&$form, \Drupal\Core\Form\FormStateInterface $form_state) {
  print $form_state->getTriggeringElement()['#name'];
}