Use the `numberInput()` function to create number inputs in your forms. It uses the HTML `` element which provides built-in number validation.
***
## Basic usage
```javascript
import { Composer } from "formsmd";
const composer = new Composer({
id: "my-form"
});
composer.numberInput("quantity", {
question: "How many items would you like?"
});
```
Generates the following Markdown-like syntax:
```
#! id = my-form
quantity = NumberInput(
| question = How many items would you like?
)
```
### Required
Add the `required` parameter to make the field mandatory:
```javascript
composer.numberInput("quantity", {
question: "How many items would you like?",
required: true
});
```
Generates the following Markdown-like syntax:
```
quantity* = NumberInput(
| question = How many items would you like?
)
```
***
## Function overview
The following is the overview of the function:
```typescript
numberInput(name: string, params: object)
```
### Arguments
| Name | Type | Description |
| -------- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `name` | `string` | A unique name for your form field that you'll use to identify the user's response.\* |
| `params` | `object` | An object containing all the configuration parameters for your number input field (see the [parameters section](#parameters) below for the full list of options). |
{% hint style="danger" %} \*Avoid values for the `name` argument which may be the names of HTML attributes, such as `"name"`, `"role"`, `"id"`, etc. This is because by default, the form's template string is first sanitized using [DOMPurify](https://github.com/cure53/DOMPurify), and these values may be removed to prevent DOM clobbering.
{% endhint %}
***
## Parameters
### Shared parameters
These parameters are common to all form fields:
| Name | Type | Description |
| --------------------- | ----------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `question` (required) | `string` | The main question or label of the form field. |
| `required` | `true` (`boolean`) | When set, the field becomes required. |
| `description` | `string` | Any extra information that the user may need to fill out the form. Appears right below the question. |
| `fieldSize` | `"sm"` | When set to `"sm"`, the font sizes of the question, description, and answer are made smaller. |
| `labelStyle` | `"classic"` | When set to `"classic"`, the question and description of the form field are made smaller. |
| `subfield` | `true` (`boolean`) | When set, the question and description of the form field are made smaller. Functionally the same as setting `labelStyle` to `"classic"`. |
| `disabled` | `true` (`boolean`) | When set, the input is disabled. |
| `autofocus` | `true` (`boolean`) | When set, the input will be automatically focused when the parent slide becomes active, or immediately after page load. |
| `id` | `string` | The `id` attribute of the form field container. |
| `classNames` | `string[]` | The CSS class names of the form field. [See the available CSS utility classes](https://docs.forms.md/content/css-utility-classes). |
| `attrs` | `Array<{ name: string, value: string }>` | Other HTML attributes of the form field. Each attribute has a `name` and `value` property. |
| `displayCondition` | `{ dependencies: string[], condition: string }` | Controls when the field is shown. The `dependencies` lists the fields to watch, and `condition` is the expression that must be true to show the field. The `condition` must be a valid [Nunjucks](https://mozilla.github.io/nunjucks/) expression. [See example](#conditional-display). |
### Number input specific parameters
| Name | Type | Description |
| ------------- | -------- | ----------------------------------------------------------------------------------- |
| `placeholder` | `string` | Sets the `placeholder` attribute of the input. |
| `min` | `number` | Sets the minimum allowed value. |
| `max` | `number` | Sets the maximum allowed value. |
| `step` | `number` | Sets the stepping interval. |
| `unit` | `string` | Text to display before the input as a unit (e.g., `"$"`, `"€"`). Purely decorative. |
| `unitEnd` | `string` | Text to display after the input as a unit (e.g., `"kg"`, `"%"`). Purely decorative. |
| `value` | `number` | If set, this becomes the default value of the input. |
***
## Examples
### Number input with range limits
```javascript
composer.numberInput("age", {
question: "What is your age?",
description: "Must be 18 or older to participate",
min: 18,
max: 120,
required: true
});
```
Generates the following Markdown-like syntax:
```
age* = NumberInput(
| question = What is your age?
| description = Must be 18 or older to participate
| min = 18
| max = 120
)
```
### Number input with unit
```javascript
composer.numberInput("price", {
question: "Enter the price",
unit: "$",
step: 0.01,
min: 0,
required: true
});
```
Generates the following Markdown-like syntax:
```
price* = NumberInput(
| question = Enter the price
| unit = $
| step = 0.01
| min = 0
)
```
### Styled number input with custom attributes
Add CSS classes and other HTML attributes using the `classNames` and `attrs` parameters. Please note, these class names and attributes are added to the `
