Basic functionality

Form API example

Notes on 3.x:

• The #data-orientation is replaced with #orientation. You can still use #data-orientation but it will be deprecated soon.
• A a new #dir attribute is available defaulting to ltr

$form['example'] = [
  '#type' => 'range_slider',
  '#title' => 'Rangeslider element',
  '#min' => 5,
  '#max' => 30,
  '#step' => 2,
  '#default_value' => 12,
  '#description' => 'Example range slider form element.',
  '#dir' => 'rtl', // Only available in 3.x
  '#orientation' => 'horizontal', // Only available in 3.x
  '#data-orientation' => 'horizontal',
  '#output' => 'below',
  '#output__field_prefix' => '$',
  '#output__field_suffix' => 'USD',
];