# How To >> Extend a native Input ||20 ```js script import { html } from '@lion/core'; import { LionInput } from '@lion/input'; import { LionInputDate } from '@lion/input-date'; import { loadDefaultFeedbackMessages } from '@lion/validate-messages'; import '@lion/input/define'; import '../../docs/systems/form/assets/h-output.js'; loadDefaultFeedbackMessages(); ``` Input fields can be created by extending [LionInput](../../components/inputs/input/overview.md). > In case you want to wrap a custom form element, follow [Create a custom Field](./create-a-custom-field.md). For this tutorial, we create an input that wraps native `input[type=datetime-local]`. This is as simple as adding a type: ```js preview-story export const extendLionInput = () => { class LionInputDatetime extends LionInput { constructor() { super(); this.type = 'datetime-local'; } } customElements.define('lion-input-datetime', LionInputDatetime); return html` `; }; ``` However, we might want to have a more advanced modelValue. In the example above, our modelValue is a serialized datetime string. If we want our modelValue to be of type Date, we should do the following: ```js preview-story export const extendLionInputDate = () => { function toIsoDatetime(d) { return d && new Date(d.getTime() - d.getTimezoneOffset() * 60000).toISOString().split('.')[0]; } function fromIsoDatetime(value) { return new Date(value); } class LionInputDatetimeWithObject extends LionInputDate { constructor() { super(); this.type = 'datetime-local'; this.parser = fromIsoDatetime; this.deserializer = fromIsoDatetime; this.serializer = toIsoDatetime; this.formatter = toIsoDatetime; } } customElements.define('lion-input-datetime-with-object', LionInputDatetimeWithObject); return html` `; }; ```