Currency formatter for adding commas for silly humans

format_currency.js

/****************************/
/* Author: Deac Karns
/* Date: 2017-03-10
/****************************/

// Useage:
// var num = 1234567.89
//
// console.log( num.currency() );
//
// output: 1,234,567.89


String.prototype.currency = function () {
  return this.replace(/[^0-9.]/g, "")
    .replace(/(^|[^\w.])(\d{4,})/g, function($0, $1, $2) {
      return $1 + $2.replace(/\d(?=(?:\d\d\d)+(?!\d))/g, "$&,");
    });
}

Number.prototype.currency = function () {
  return String(this).currency();
}

format_currency.php

public static function toCurrency($value)
{
  $clear = preg_replace('/[^0-9.]/', '', $value);
  return preg_replace('/\B(?=(\d{3})+(?!\d))/', ',', $clear);
}