How to convert Persian and Arabic digits of a string to English using JavaScript?

How can I convert Persian/Arabic numbers to English numbers with a simple function?

arabicNumbers = ["١", "٢", "٣", "٤", "٥", "٦", "٧", "٨", "٩", "٠"]
persianNumbers = ["۱", "۲", "۳", "۴", "۵", "۶", "۷", "۸", "۹", "۰"]

It is the same schema, but the code pages are different.

Solution 1:

Use this simple function to convert your string

var
persianNumbers = [/۰/g, /۱/g, /۲/g, /۳/g, /۴/g, /۵/g, /۶/g, /۷/g, /۸/g, /۹/g],
arabicNumbers  = [/٠/g, /١/g, /٢/g, /٣/g, /٤/g, /٥/g, /٦/g, /٧/g, /٨/g, /٩/g],
fixNumbers = function (str)
{
  if(typeof str === 'string')
  {
    for(var i=0; i<10; i++)
    {
      str = str.replace(persianNumbers[i], i).replace(arabicNumbers[i], i);
    }
  }
  return str;
};

Be careful, in this code the persian numbers codepage are different with the arabian numbers.

Example

var mystr = 'Sample text ۱۱۱۵۱ and ٢٨٢٢';
mystr = fixNumbers(mystr);

Refrence

Solution 2:

Oneliner of all 6 possible translations between English, Arabic, and persian Digits.

const e2p = s => s.replace(/\d/g, d => '۰۱۲۳۴۵۶۷۸۹'[d])
const e2a = s => s.replace(/\d/g, d => '٠١٢٣٤٥٦٧٨٩'[d])

const p2e = s => s.replace(/[۰-۹]/g, d => '۰۱۲۳۴۵۶۷۸۹'.indexOf(d))
const a2e = s => s.replace(/[٠-٩]/g, d => '٠١٢٣٤٥٦٧٨٩'.indexOf(d))

const p2a = s => s.replace(/[۰-۹]/g, d => '٠١٢٣٤٥٦٧٨٩'['۰۱۲۳۴۵۶۷۸۹'.indexOf(d)])
const a2p = s => s.replace(/[٠-٩]/g, d => '۰۱۲۳۴۵۶۷۸۹'['٠١٢٣٤٥٦٧٨٩'.indexOf(d)])

e2p("asdf1234") // asdf۱۲۳۴
e2a("asdf1234") // asdf١٢٣٤
p2e("asdf۱۲۳۴") // asdf1234
a2e("asdf١٢٣٤") // asdf1234
p2a("asdf۱۲۳۴") // asdf١٢٣٤
a2p("asdf١٢٣٤") // asdf۱۲۳۴

Explaination:

(s => f(s))(x) is a lambda function that is immediately executed, and will be equal to f(x)
s.replace(pattern, function) looks for matches of pattern in s, for every match m it will replace m with function(m) in the string.
/\d/g is a regex pattern, \d means a digit in the English language, g means global. If you don't specify the g it will only match the first occurrence, otherwise it will match all the occurrences.
In this case for every English digit d in the string, that digit will be replaced by '۰۱۲۳۴۵۶۷۸۹'[d] so, 3 will be replaced by the third index in that list('۰۱۲۳۴۵۶۷۸۹') which is '۳'
/[۰-۹]/g is the equivalent regex for Persian digits this time we can't use the same method, before we took advantage of the fact that javascript is dynamically typed and that d is automatically converted from a string(regex match) to a number(array index) (you can do '1234'['1'] in javascript which is the same as '1234'[1])
but this time we can't do that because '1234'['۱'] is invalid. so we use a trick here and use indexOf which is a function that tells us the index of an element in an array(here a character in a string) so, '۰۱۲۳۴۵۶۷۸۹'.indexOf(۳) will give us 3 because '۳' is the third index in the string '۰۱۲۳۴۵۶۷۸۹'

Solution 3:

this is a simple way to do that:

function toEnglishDigits(str) {

    // convert persian digits [۰۱۲۳۴۵۶۷۸۹]
    var e = '۰'.charCodeAt(0);
    str = str.replace(/[۰-۹]/g, function(t) {
        return t.charCodeAt(0) - e;
    });

    // convert arabic indic digits [٠١٢٣٤٥٦٧٨٩]
    e = '٠'.charCodeAt(0);
    str = str.replace(/[٠-٩]/g, function(t) {
        return t.charCodeAt(0) - e;
    });
    return str;
}

an example:

console.log(toEnglishDigits("abc[0123456789][٠١٢٣٤٥٦٧٨٩][۰۱۲۳۴۵۶۷۸۹]"));
// expected result => abc[0123456789][0123456789][0123456789]