Restricted Input

 

Allow restricted character sets in input elements.

Demo

Try the latest version of Restricted Input here.

Features

- Disallow arbitrary characters based on patterns
- Maintains caret position
- Format/Update on paste
- Works in IE11+

Development

Install dependencies

``bash
nvm use # if you have node version manager installed
npm i
`

Watch files and run demo server

`bash
npm run development
`

This will start a server on port 3099 which can be overridden with the PORT env var.

Unit tests

The following command will run the linting task and the unit tests.

`sh
npm test
`

Integration tests

We use Browserstack to automate end to end testing on Google Chrome, Safari, Firefox, Microsoft Edge, and Internet Explorer 11.

First, sign up for a free open source Browserstack account.

Copy the .env.example file to .env

`sh
cp .env.example .env
`

Fill in the BROWSERSTACK_USERNAME and BROWSERSTACK_ACCESS_KEY environmental variables with your credentials:

`sh
BROWSERSTACK_USERNAME=username
BROWSERSTACK_ACCESS_KEY=access_key
`

To run the integration tests in Safari, Google Chrome, Firefox, IE11 and Microsoft Edge:

`sh
npm run development # in another terminal window
npm run test:integration
`

To run tests in only one browser, prefix the test command with an ONLY_BROWSERS env variable:

`sh


run only in edge browser

ONLY_BROWSERS=edge npm run test:integration

run only in chrome browser

ONLY_BROWSERS=chrome npm run test:integration

run only in ie 11 browser

ONLY_BROWSERS=ie npm run test:integration

run only in safari browser

ONLY_BROWSERS=safari npm run test:integration

run only in firefox browser

ONLY_BROWSERS=firefox npm run test:integration
`

To run tests in certain browsers, prefix the test command with an ONLY_BROWSERS env variable, with each browser comma separated:

`sh


run only in edge and chrome browsers


ONLY_BROWSERS=edge,chrome npm run test:integration
`

To run only certain tests, add the .only property before running the test:

`js
it.only('does something', function () {
`

Usage

`javascript
import RestrictedInput from "restricted-input";

const formattedCreditCardInput = new RestrictedInput({
element: document.querySelector("#credit-card"),
pattern: "{{9999}} {{9999}} {{9999}} {{9999}}",
});
`

Patterns

Patterns are a mixture of Placeholders and PermaChars.

$3

A Placeholder is the part of the pattern that accepts user input based on some restrictions. A placeholder is defined in the pattern using two open curly brackets, the placeholder, followed by two closing curly brackets e.g. {{Abc123}}.

The patterns a Placeholder can be are:

- a single alpha character that matches the alpha regex /[A-Za-z]/. e.g. {{C}} will match one alpha character.
- a single digit that matches the digit regex /[0-9]/. e.g. {{3}} will match one digit.
- a character that matches /./. e.g. {{}} will match the next character.

$3

A PermaChar is the part of the pattern that is automatically inserted. PermaChars are defined in the pattern as any characters other than Placeholders.

$3

Some example patterns with behavior are listed:

- 12{{3}}
- Inserts 12.
- Waits for a single digit from the user.
- {{A}}BC
- Waits for a single alpha from the user.
- Inserts BC.
- ${{*2L}}E
- Inserts $.
- Waits for any single character input from the user.
- Waits for a single digit from the user.
- Waits for a single alpha from the user.
- Inserts E.

Paste Event

If an input is changed via a paste event, you may want to adjust the pattern before input formatting occurs. In this case, pass an onPasteEvent callback:

`js
const formattedCreditCardInput = new RestrictedInput({
element: document.querySelector('#credit-card'),
pattern: '{{9999}} {{9999}} {{9999}} {{9999}}',
onPasteEvent: function (payload) {
var value = payload.unformattedInputValue;

if (requiresAmexPattern(value)) {
formattedCreditCardInput.setPattern('{{9999}} {{999999}} {{99999}}')
} else {
formattedCreditCardInput.setPattern('{{9999}} {{9999}} {{9999}} {{9999}}')
}
})
});
`

API

$3

| Key | Type | Description |
| ------------ | ------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------ |
| element | HTMLInputElement or HTMLTextAreaElement | A valid reference to an input or textarea DOM node |
| pattern | String | Pattern describing the allowed character set you wish for entry into corresponding field. See Patterns. |
| onPasteEvent | Function` (optional) | A callback function to inspect the unformatted value of the input during a paste event. See Paste Event. |

Browser Support

Desktop

- Chrome (latest)
- Firefox (17+)
- Safari (8+)
- IE11 (desktop/metro)
- IE10 (desktop/metro)
- IE9

Browsers Where Formatting is Turned Off Automatically

Old versions of Samsung Android browsers are incompatible with formatting. These will not attempt to intercept the values and format the input.

TODO

- [ ] Improve jsdoc
- [ ] Add example guides/pages