react-number-format

What is react-number-format?

The react-number-format package is a React component designed for formatting number input fields. It allows users to format numbers as currency, percentages, decimals, phone numbers, credit card numbers, and other custom formats. It also supports features like custom prefix, suffix, and thousand separator, masking, and custom formatting.

What are react-number-format's main functionalities?

Number Formatting

This feature allows you to format numbers with thousands separators and add a prefix. In this example, the number 2456981 is formatted as currency with a dollar sign prefix and commas as thousand separators, displayed as $2,456,981.

import NumberFormat from 'react-number-format';

<NumberFormat value={2456981} displayType={'text'} thousandSeparator={true} prefix={'$'} />

Custom Format

This feature enables custom formatting for inputs. Here, the format prop defines the pattern for a phone number and the mask prop is used for placeholder characters, allowing users to enter a phone number in the format ###-###-####.

import NumberFormat from 'react-number-format';

<NumberFormat format="###-###-####" mask="_" />

Currency Formatting

This feature is used to format input as currency. It includes a thousand separator, a dollar sign prefix, and ensures that there are always two decimal places.

import NumberFormat from 'react-number-format';

<NumberFormat thousandSeparator={true} prefix={'$'} decimalScale={2} fixedDecimalScale={true} />

Other packages similar to react-number-format

cleave.js

Cleave.js is a library that can format input text content when you are typing. It provides similar functionalities to react-number-format, such as number formatting, credit card formatting, phone number formatting, and date formatting. It differs in that it is not React-specific and can be used with plain JavaScript or other frameworks.

numeral

Numeral is a library for formatting and manipulating numbers. It's similar to react-number-format in that it can format numbers as currency, percentages, and other formats. However, it is not a React component and does not handle input fields directly. It is more focused on number manipulation and formatting in general JavaScript applications.

currency.js

Currency.js is a small and lightweight library for working with currency values. It allows you to perform arithmetic operations and formatting on currency numbers. While it provides similar currency formatting capabilities, it does not come as a React component and is more suited for general arithmetic and formatting operations rather than handling user input.

README

react-number-format

React component to format number in an input or as a text

Features

1. Prefix, suffix and thousand separator.
2. Custom format pattern.
3. Masking.
4. Custom formatting handler.
5. Formatting a input or a simple text.

Install

Through npm npm install react-number-format --save

Or get compiled development and production version from ./dist

Props

Props	Options	Default	Description
thousandSeparator	mixed: single character string or boolean true (true is default to ,)	none	Add thousand separators on number
decimalSeparator	single character string	.	Support decimal point on a number
decimalPrecision	number	none	If defined it limits to given decimal precision
allowNegative	boolean	true	allow negative numbers (Only when format option is not provided)
prefix	String (ex : $)	none	Add a prefix before the number
suffix	String (ex : /-)	none	Add a prefix after the number
value	Number or String	null	Value to the number format. If passed as string it should have same decimal separator as the decimalSeparator props
displayType	String: text / input	input	If input it renders a input element where formatting happens as you input characters. If text it renders it as a normal text in a span formatting the given value
type	One of ['text', 'tel']	text	Input type attribute
format	String : Hash based ex (#### #### #### ####) Or Function	none	If format given as hash string allow number input inplace of hash. If format given as function, component calls the function with unformatted number and expects formatted number.
mask	String (ex : _)	none	If mask defined, component will show non entered placed with masked value.
customInput	Component Reference	input	This allow supporting custom inputs with number format.
onChange	(e, values) => {}	none	onChange handler accepts event object and values object
isAllowed	(values) => true or false	none	A checker function to check if input value is valid or not

Other than this it accepts all the props which can be given to a input or span based on displayType you selected.

values object

values object is on following format

{
  formattedValue: '$23,234,235.56', //value after applying formatting
  value: '23234235.56', //non formatted value as string, but it maintains the decimalSeparator provided, so if , is decimal separator then value will be 23234235,56
  floatValue: 23234235.56 //floating point representation. For big numbers it can have exponential syntax
}

Notes and quirks

1. Value can be passed as string or number, but if it is passed as string you should maintain the same decimal separator on the string what you provided as decimalSeparator prop.

2. Value as prop will be rounded to given precision if format option is not provided.

3. If you want to block floating number set decimalPrecision to 0.

4. Use type as tel when you are providing format prop. This will change the mobile keyboard layout to have only numbers. In other case use type as text, so user can type decimal separator.

Examples

Prefix and thousand separator : Format currency as text

var NumberFormat = require('react-number-format');

<NumberFormat value={2456981} displayType={'text'} thousandSeparator={true} prefix={'$'} />

Output : $2,456,981

Format with pattern : Format credit card as text

<NumberFormat value={4111111111111111} displayType={'text'} format="#### #### #### ####" />

Output : 4111 1111 1111 1111

Prefix and thousand separator : Format currency in input

<NumberFormat thousandSeparator={true} prefix={'$'} />

Maintaining change value on state

<NumberFormat value={this.state.profit} thousandSeparator={true} prefix={'$'} onChange={(e, values) => {
    const {formattedValue, value} = values;
    // formattedValue = $222,3
    //value ie, 2223
    this.setState({profit: value})
  }}/>

Format with pattern : Format credit card in an input

<NumberFormat format="#### #### #### ####" />

Format with mask : Format credit card in an input

<NumberFormat format="#### #### #### ####" mask="_"/>

Custom format method : Format credit card expiry time

function limit(val, max) {
  if (val.length === 1 && val[0] > max[0]) {
    val = '0' + val;
  }

  if (val.length === 2) {
    if (Number(val) === 0) {
      val = '01';

    //this can happen when user paste number
  } else if (val > max) {
      val = max;
    }
  }

  return val;
}

function cardExpiry(val) {
  let month = limit(val.substring(0, 2), '12');
  let date = limit(val.substring(2, 4), '31');

  return month + (date.length ? '/' + date : '');
}

<NumberFormat format={cardExpiry}/>

Custom Inputs

You can easily extend your custom input with number format. But custom input should have all input props.

  import TextField from 'material-ui/TextField';

  <NumberFormat customInput={TextField} format="#### #### #### ####"/>

Passing custom input props All custom input props and number input props are passed together.

  <NumberFormat hintText="Some placeholder" value={this.state.card} customInput={TextField} format="#### #### #### ####"/>

Live Demo

http://codepen.io/s-yadav/pen/bpKNMa

Major Updates

v2.0.0

• Added isAllowed prop to validate custom input and block based on it.
• onChange api been changed. Now it receives values object as second parameter.
• decimalSeparator no longer support boolean values
• thousandSeparator accepts only true as boolean (which defaults to ,) or thousandSeparator string
• decimalSeparator only accepts number Now
• Value can be passed as string or number but if it is passed as string you should maintain the same decimal separator on the string what you provided as decimalSeparator prop.
• Added back the type prop for the input type attribute (Only text or tel is supported)
• Lot of bugs and stability fixes (See release notes)

Development

• Download the zip
• npm install
• npm start to run example server
• npm run test to test changes
• npm run bundle to bundle files

Testing

Test cases are written in jasmine and run by karma Test file : /test/test_input.js To run test : npm run test