payment.js v

Payment

A jQuery-free general purpose library for building credit card forms, validating inputs and formatting numbers. Heavily, heavily based on @stripe's jquery.payment library, but without the jQuery.

For example, you can make a input act like a credit card field (with number formatting and length restriction):

Payment.formatCardNumber(document.querySelector('input.cc-num'));

Then, when the payment form is submitted, you can validate the card number on the client-side:

var valid = Payment.fns.validateCardNumber(document.querySelector('input.cc-num').value);

if (!valid) {
  alert('Your card is not valid!');
  return false;
}

You can find a full demo here.

Supported card types are:

• Visa
• MasterCard
• American Express
• Discover
• JCB
• Diners Club
• Maestro
• Laser
• UnionPay

API

Payment.formatCardNumber

Formats card numbers:

• Includes a space between every 4 digits
• Restricts input to numbers
• Limits to 16 numbers
• Supports American Express formatting
• Adds a class of the card type (e.g. 'visa') to the input

Example:

Payment.formatCardNumber(document.querySelector('input.cc-num'));

Payment.formatCardExpiry

Formats card expiry:

• Includes a / between the month and year
• Restricts input to numbers
• Restricts length

Example:

Payment.formatCardExpiry(document.querySelector('input.cc-exp'));

Payment.formatCardCVC

Formats card CVC:

• Restricts length to 4 numbers
• Restricts input to numbers

Example:

Payment.formatCardCVC(document.querySelector('input.cc-cvc'));

Payment.restrictNumeric

General numeric input restriction.

Example:

Payment.restrictNumeric(document.querySelector('[data-numeric]'));

Payment.fns.validateCardNumber(number)

Validates a card number:

• Validates numbers
• Validates Luhn algorithm
• Validates length

Example:

Payment.fns.validateCardNumber('4242 4242 4242 4242'); //=> true

Payment.fns.validateCardExpiry(month, year)

Validates a card expiry:

• Validates numbers
• Validates in the future
• Supports year shorthand

Example:

Payment.fns.validateCardExpiry('05', '20'); //=> true
Payment.fns.validateCardExpiry('05', '2015'); //=> true
Payment.fns.validateCardExpiry('05', '05'); //=> false

Payment.fns.validateCardCVC(cvc, type)

Validates a card CVC:

• Validates number
• Validates length to 4

Example:

Payment.fns.validateCardCVC('123'); //=> true
Payment.fns.validateCardCVC('123', 'amex'); //=> true
Payment.fns.validateCardCVC('1234', 'amex'); //=> true
Payment.fns.validateCardCVC('12344'); //=> false

Payment.fns.cardType(number)

Returns a card type. Either:

• visa
• mastercard
• discover
• amex
• jcb
• dinersclub
• maestro
• laser
• unionpay

The function will return null if the card type can't be determined.

Example:

Payment.fns.cardType('4242 4242 4242 4242'); //=> 'visa'

Payment.fns.cardExpiryVal(string) and Payment.cardExpiryVal(el)

Parses a credit card expiry in the form of MM/YYYY, returning an object containing the month and year. Shorthand years, such as 13 are also supported (and converted into the longhand, e.g. 2013).

Payment.fns.cardExpiryVal('03 / 2025'); //=> {month: 3: year: 2025}
Payment.fns.cardExpiryVal('05 / 04'); //=> {month: 5, year: 2004}
Payment.fns.cardExpiryVal(document.querySelector('input.cc-exp')) //=> {month: 4, year: 2020}

This function doesn't perform any validation of the month or year; use Payment.fns.validateCardExpiry(month, year) for that.

Example

Look in ./example/index.html

Building

Run gulp build

Running tests

Run gulp test

Autocomplete recommendations

We recommend you turn autocomplete on for credit card forms, except for the CVC field. You can do this by setting the autocomplete attribute:

<form autocomplete="on">
  <input class="cc-number">
  <input class="cc-cvc" autocomplete="off">
</form>

You should also mark up your fields using the Autocomplete Types spec. These are respected by a number of browsers, including Chrome.

<input type="text" class="cc-number" pattern="\d*" autocompletetype="cc-number" placeholder="Card number" required>

Set autocompletetype to cc-number for credit card numbers, cc-exp for credit card expiry and cc-csc for the CVC (security code).

Mobile recommendations

We recommend you set the pattern attribute which will cause the numeric keyboard to be displayed on mobiles:

<input class="cc-number" pattern="\d*">

You may have to turn off HTML5 validation (using the novalidate form attribute) when using this pattern, as it won't match space formatting.