osipkd.js

function addCommas(nStr)
{
  nStr += '';
  x = nStr.split('.');
  x1 = x[0];
  x2 = x.length > 1 ? '.' + x[1] : '';
  var rgx = /(\d+)(\d{3})/;
  while (rgx.test(x1)) {
    x1 = x1.replace(rgx, '$1' + ',' + '$2');
  }
  return x1 + x2;
}

Number.prototype.formatMoney = function(decPlaces, thouSeparator, decSeparator) {
  var n = this,
      decPlaces = isNaN(decPlaces = Math.abs(decPlaces)) ? 2 : decPlaces,
      decSeparator = decSeparator == undefined ? "." : decSeparator,
      thouSeparator = thouSeparator == undefined ? "," : thouSeparator,
      sign = n < 0 ? "-" : "",
      i = parseInt(n = Math.abs(+n || 0).toFixed(decPlaces)) + "",
      j = (j = i.length) > 3 ? j % 3 : 0;
  return sign + (j ? i.substr(0, j) + thouSeparator : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + thouSeparator) + (decPlaces ? decSeparator + Math.abs(n - i).toFixed(decPlaces).slice(2) : "");
};