Provides a form element for storage of internal information. Unlike

Provides a render element for a group of form elements. Usage example:

public static Radios::processRadios(&$element, FormStateInterface $form_state

public static StatusMessages::generatePlaceholder(array $element)

public Tableselect::getInfo() Returns

Provides a form element for double-input of passwords. Formats as a pair of password fields, which do not validate unless the two entered passwords

public static Number::validateNumber(&$element, FormStateInterface $form_state

public static RenderElement::setAttributes(&$element, $class

Provides a one-line text field form element. Properties: #maxlength: Maximum number of

Defines the max length for an email address The maximum length of an email address is 254 characters. RFC 3696 specifies a total length of 320