Date input

Create date inputs in your forms.

Date input

Use the dateInput() function to create date inputs in your forms. It uses the HTML <input type="date"> element which provides built-in date selection and validation.

---

Basic usage

import { Composer } from "formsmd";

const composer = new Composer({
  id: "my-form"
});

composer.dateInput("birthdate", {
  question: "What is your birth date?"
});

Generates the following Markdown-like syntax:

#! id = my-form

birthdate = DateInput(
  | question = What is your birth date?
)

Required

Add the required parameter to make the field mandatory:

composer.dateInput("birthdate", {
  question: "What is your birth date?",
  required: true
});

Generates the following Markdown-like syntax:

birthdate* = DateInput(
  | question = What is your birth date?
)

---

Function overview

The following is the overview of the function:

dateInput(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 date input field (see the parameters section below for the full list of options).

*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, and these values may be removed to prevent DOM clobbering.

---

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.
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 expression. See example.

Date input specific parameters

Name	Type	Description
placeholder	string	Sets the placeholder attribute of the input.
min	string	Sets the minimum allowed date value ("YYYY-MM-DD").
max	string	Sets the maximum allowed date value ("YYYY-MM-DD").
step	string	Sets the stepping interval.
value	string	Pre-selected date value ("YYYY-MM-DD").

---

Examples

Date input with validation

composer.dateInput("appointmentDate", {
  question: "When would you like to schedule your appointment?",
  description: "Please select a date within the next 30 days",
  min: "2024-01-12",
  max: "2024-02-12",
  required: true
});

Generates the following Markdown-like syntax:

appointmentDate* = DateInput(
  | question = When would you like to schedule your appointment?
  | description = Please select a date within the next 30 days
  | min = 2024-01-12
  | max = 2024-02-12
)

Date input with default value

composer.dateInput("startDate", {
  question: "Start date",
  description: "When would you like to begin?",
  value: "2024-01-12"
});

Generates the following Markdown-like syntax:

startDate = DateInput(
  | question = Start date
  | description = When would you like to begin?
  | value = 2024-01-12
)

Styled date 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 <div> or <fieldset> container that contains the actual input field(s).

composer.dateInput("eventDate", {
  question: "Event date",
  classNames: ["col-6", "xs:col-6"],
  attrs: [
    { name: "style", value: "font-size: 18px;" }
  ]
});

Generates the following Markdown-like syntax:

[.col-6 .xs:col-6 style="font-size: 18px;"]
eventDate = DateInput(
  | question = Event date
)

Please see the available CSS utility classes.

Conditional display

Conditionally show or hide a date input field using the displayCondition parameter. It works as follows:

• dependencies lists the fields to watch.

• condition is the expression that must be true to show the field. This must be a valid Nunjucks expression.

For instance, in the example below, the return date input will only show up if the user indicates they want to book a round trip.

composer.choiceInput("tripType", {
  question: "What type of trip would you like to book?",
  required: true,
  choices: ["One-way", "Round trip"]
})

composer.dateInput("returnDate", {
  question: "Return date",
  displayCondition: {
    dependencies: ["tripType"],
    condition: "tripType == 'Round trip'"
  }
});

Generates the following Markdown-like syntax:

tripType* = ChoiceInput(
  | question = What type of trip would you like to book?
  | choices = One-way, Round trip
)

::: [{$ tripType $}]
{% if tripType == "Round trip" %}
returnDate = DateInput(
  | question = Return date
)
{% endif %}
:::