Convert numbers to FA/EN

fa.en.numbers.js

/**
 * Convert English numbers to Persian.
 *
 * @param {string} value
 * @return {string} converted string.
 */            
function faNumbers(value) {
  var englishNumbers = {
    '0': '۰', '1': '۱', '2': '۲', '3': '۳', '4': '۴',
    '5': '۵', '6': '۶', '7': '۷', '8': '۸', '9': '۹'
  };
  
  if (typeof value === "number") {
    var value = value.toString(); 
  }

  return value.split("").reduce(function(result, char) {
    if (char in englishNumbers) {
      return result + englishNumbers[char]
    }
    return result + char;
  }, "");
}

/**
 * Convert Persian/Arabic numbers to English.
 *
 * @param {string} value
 * @return {string} converted string.
 */    
function enNumbers(value) {
  var persianNumbers = {
    '۰': '0', '۱': '1', '۲': '2', '۳': '3', '۴': '4',
    '۵': '5', '۶': '6', '۷': '7', '۸': '8', '۹': '9',
    // in case you type with arabic keyboard:
    '٠': '0', '١': '1', '٢': '2', '٣': '3', '٤': '4',
    '٥': '5', '٦': '6', '٧': '7', '٨': '8', '٩': '9'
  };

  return value.split("").reduce(function(result, char) {
    if (char in persianNumbers) {
      return result + persianNumbers[char]
    }
    return result + char;
  }, "");
}



var log = console.log;

log(enNumbers("٠١٢٣٤٥٦٧٨٩")); // arabic
log(enNumbers("۰۱۲۳۴۵۶۷۸۹.")); // persian

log(faNumbers("0123456789"));
log(faNumbers("a123.44.51n"));
log(faNumbers("1397/10/01"));
log(faNumbers("1397-03-25"));
log(faNumbers("600,000,000"));
log(faNumbers(1234567890));  // by int input.

@nainemom

and this would be the implementation for converting english numbers to persian:

function faNumbers(str) {
  return str.toString().split('').reduce(function(result, char) {
      var charCode = char.charCodeAt(0)
      if (charCode >= 48 && charCode <= 57) { // when charachter is 0 to 9
          return result + String.fromCharCode(charCode + 1728)
      }
      return result + char;
  }, "");
}

nice fix. i also realized that toString method make it slower. maybe helper functions like this should be strict for type of parameters entered by end users.

@nainemom

toString is not needed for enNumbers(). the value that comes in enNumbers() is always a string. you cant have (۱۲۳).toString(). its always like "۱۲۳" in the first place...
however, its needed for faNumbers(). the (123).toString is actually a possible value.

and also, the || should be && in the first if. i upload a whole new script based on your solution:

https://gist.github.com/amrza/9b5940b102286f9f37160b5e2b7e81a0