coerceNumber

Coerce numeric strings into JavaScript Numbers.

Installation

npm install coerce-number

API

String to Number

stringToNumber(check, value, isNaNValue)

Argument	Description
check	An object with a test function, like RegExp, that returns true or false if a value can be converted
value	The source value to coerce
isNaNValue	(optional) The value to return if value cannot be coerced. Default is to return value.

checkFunctions

The library exports various predicate functions in coerceNumber.checkFunctions that can be used as the check argument for stringToNumber

isIntegerCheck: If a value is a whole number (positive or negative)

isPositiveIntegerCheck: If a value is a positive whole number (>= 0)

isFloatCheck: If a value is a number, with or without a decimal

isPositiveFloatCheck: If a value is a positive number, with or without a decimal

Pre-defined check functions

The following functions are exported as stringToNumber with a check function already provided:

toInteger

  const one = coerceNumber.toInteger('1'); // one = 1
  const minusOne = coerceNumber.toInteger('-1'); // one = -1
  const onePointOne = coerceNumber.toInteger('1.1'); // onePointOne = '1.1'
  const minusOnePointOne = coerceNumber.toInteger('-1.1'); // onePointOne = '-1.1'

toPositiveInteger

  const one = coerceNumber.toPositiveInteger('1'); // one = 1
  const minusOne = coerceNumber.toPositiveInteger('-1'); // one = '-1'
  const onePointOne = coerceNumber.toPositiveInteger('1.1'); // onePointOne = '1.1'
  const minusOnePointOne = coerceNumber.toPositiveInteger('-1.1'); // onePointOne = '-1.1'

toFloat

  const one = coerceNumber.toFloat('1'); // one = 1
  const minusOne = coerceNumber.toFloat('-1'); // one = -1
  const onePointOne = coerceNumber.toFloat('1.1'); // onePointOne = 1.1
  const minusOnePointOne = coerceNumber.toFloat('-1.1'); // onePointOne = -1.1

toPositiveFloat

  const one = coerceNumber.toPositiveFloat('1'); // one = 1
  const minusOne = coerceNumber.toPositiveInteger('-1'); // one = '-1'
  const onePointOne = coerceNumber.toInteger('1.1'); // onePointOne = 1.1
  const minusOnePointOne = coerceNumber.toInteger('-1.1'); // onePointOne = '-1.1'

Map

This function iterates over arrays and objects and applies a transform to all string values.

map(value, iteratee)

iteratee is a functions that takes a string and returns a replacement value. Default is toFloat

  const coerceNumber = require('coerce-number');
  const data = {
    id: '1',
    currency: 'USD',
    cost: '10',
    tax: '0.8'
  };
 
  const numericData = coerceNumber.map(data);
  /*
  numericData = {
    id: 1,
    currency: 'USD',
    cost: 10,
    tax: 0.8
  };
  */