37 classes are annotated with FormElement in Drupal 8

Button in core/lib/Drupal/Core/Render/Element/Button.php

Provides an action button form element.

Checkbox in core/lib/Drupal/Core/Render/Element/Checkbox.php

Provides a form element for a single checkbox.

Checkboxes in core/lib/Drupal/Core/Render/Element/Checkboxes.php

Provides a form element for a set of checkboxes.

Color in core/lib/Drupal/Core/Render/Element/Color.php

Provides a form element for choosing a color.

Date in core/lib/Drupal/Core/Render/Element/Date.php

Provides a form element for date selection.

Datelist in core/lib/Drupal/Core/Datetime/Element/Datelist.php

Provides a datelist element.

Datetime in core/lib/Drupal/Core/Datetime/Element/Datetime.php

Provides a datetime element.

Email in core/lib/Drupal/Core/Render/Element/Email.php

Provides a form input element for entering an email address.

EntityAutocomplete in core/lib/Drupal/Core/Entity/Element/EntityAutocomplete.php

Provides an entity autocomplete form element.

File in core/lib/Drupal/Core/Render/Element/File.php

Provides a form element for uploading a file.

Hidden in core/lib/Drupal/Core/Render/Element/Hidden.php

Provides a form element for an HTML 'hidden' input element.

ImageButton in core/lib/Drupal/Core/Render/Element/ImageButton.php

Provides a form element for a submit button with an image.

Item in core/lib/Drupal/Core/Render/Element/Item.php

Provides a display-only form element with an optional title and description.

LanguageConfiguration in core/modules/language/src/Element/LanguageConfiguration.php

Defines an element for language configuration for a single field.

LanguageSelect in core/lib/Drupal/Core/Render/Element/LanguageSelect.php

Provides a form element for selecting a language.

MachineName in core/lib/Drupal/Core/Render/Element/MachineName.php

Provides a machine name render element.

ManagedFile in core/modules/file/src/Element/ManagedFile.php

Provides an AJAX/progress aware widget for uploading and saving a file.

Number in core/lib/Drupal/Core/Render/Element/Number.php

Provides a form element for numeric input, with special numeric validation.

Password in core/lib/Drupal/Core/Render/Element/Password.php

Provides a form element for entering a password, with hidden text.

PasswordConfirm in core/lib/Drupal/Core/Render/Element/PasswordConfirm.php

Provides a form element for double-input of passwords.

PathElement in core/lib/Drupal/Core/Render/Element/PathElement.php

Provides a matched path render element.

Radio in core/lib/Drupal/Core/Render/Element/Radio.php

Provides a form element for a single radio button.

Radios in core/lib/Drupal/Core/Render/Element/Radios.php

Provides a form element for a set of radio buttons.

Range in core/lib/Drupal/Core/Render/Element/Range.php

Provides a slider for input of a number within a specific range.

Search in core/lib/Drupal/Core/Render/Element/Search.php

Provides an HTML5 input element with type of "search".

Select in core/lib/Drupal/Core/Render/Element/Select.php

Provides a form element for a drop-down menu or scrolling selection box.

Submit in core/lib/Drupal/Core/Render/Element/Submit.php

Provides a form submit button.

Table in core/lib/Drupal/Core/Render/Element/Table.php

Provides a render element for a table.

Tableselect in core/lib/Drupal/Core/Render/Element/Tableselect.php

Provides a form element for a table with radios or checkboxes in left column.

Tel in core/lib/Drupal/Core/Render/Element/Tel.php

Provides a form element for entering a telephone number.

Textarea in core/lib/Drupal/Core/Render/Element/Textarea.php

Provides a form element for input of multiple-line text.

Textfield in core/lib/Drupal/Core/Render/Element/Textfield.php

Provides a one-line text field form element.

Token in core/lib/Drupal/Core/Render/Element/Token.php

Stores token data in a hidden form field.

Url in core/lib/Drupal/Core/Render/Element/Url.php

Provides a form element for input of a URL.

Value in core/lib/Drupal/Core/Render/Element/Value.php

Provides a form element for storage of internal information.

VerticalTabs in core/lib/Drupal/Core/Render/Element/VerticalTabs.php

Provides a render element for vertical tabs in a form.

Weight in core/lib/Drupal/Core/Render/Element/Weight.php

Provides a form element for input of a weight.