[//]: # 'AUTO INSERT HEADER PREPUBLISH'
# Checkbox Group
`lion-checkbox-group` component enhances the functionality of the native `` element.
Its purpose is to provide a way for users to check **multiple** options amongst a set of choices, or to function as a single toggle.
> You should use `` elements as the children of the ``.
```js script
import { html } from '@lion/core';
import { Required, Validator } from '@lion/form-core';
import './lion-checkbox-group.js';
import './lion-checkbox.js';
export default {
title: 'Forms/Checkbox Group',
};
```
```js story
export const main = () => html`
`;
```
> Make sure that the checkbox-group also has a name attribute, this is necessary for the [lion-form](?path=/docs/forms-form-overview--main)'s serialization result.
## Features
Since it extends from [lion-fieldset](?path=/docs/forms-fieldset-overview--main),
it has all the features a fieldset has.
## How to use
### Installation
```bash
npm i --save @lion/checkbox-group
```
```js
import '@lion/checkbox-group/lion-checkbox-group.js';
import '@lion/checkbox-group/lion-checkbox.js';
```
### Model value
The `modelValue` of a `lion-checkbox-group` is an array containing the `choiceValues` of the `lion-checkbox` elements that have been checked.
Given the scientists example above, say that we were to select the first and last options
(Archimedes & Marie Curie).
Then the `modelValue` of the `lion-checkbox-group` will look as follows:
```js
const groupElement = [parent].querySelector('lion-checkbox-group');
groupElement.modelValue;
=> ["Archimedes", "Marie Curie"];
```
### The `name` attribute
The `name` attribute of a `lion-checkbox-group` automatically gets assigned to its `lion-checkbox` children. You can also specify names for the `lion-checkbox` elements, but if this name is different from the name assigned to `lion-checkbox-group`, then an exception will be thrown.
Our recommendation would be to set the `name` attribute only on the `lion-checkbox-group` and not on the `lion-checkbox` elements.
### Example
```html
```
### Pre-select
You can pre-select options by targeting the `modelValue` object of the option and setting the `checked` property to `true`.
```js preview-story
export const preselect = () => html`
`;
```
### Disabled
You can disable the entire group by setting the `disabled` attribute on the ``.
```js preview-story
export const disabled = () => html`
`;
```
### Help text
You can add help text on each checkbox with `help-text` attribute on the ``.
```js preview-story
export const helpText = () => html`
`;
```
### Event
You can listen to the `model-value-changed` event whenever the value of the checkbox group is changed.
```js preview-story
export const event = () => html`
(document.getElementById('selectedDinosaur').innerText = JSON.stringify(
e.target.modelValue,
null,
4,
))}
>
Selected scientists: N/A
`;
```