Format number with thousand separator whilst typing

format-number.js

NWS = {
  $inputForm : {},
  offset: 0,
  FormLength : 0,
  FormLengthNew : 0,
  char: ' ',

  ku: function(selector, char = ' '){

    NWS.$inputForm = $(selector);
    NWS.char = char;
    NWS.FormLength =   NWS.$inputForm.val().length;
    NWS.formatNum();


  },
  formatNum: function(){
    var start = NWS.$inputForm[0].selectionStart,
        end = NWS.$inputForm[0].selectionEnd;

          NWS.$inputForm.val(NWS.format(NWS.$inputForm.val()));
          NWS.FormLengthNew =   NWS.$inputForm.val().length;

          NWS.offset = NWS.FormLengthNew - NWS.FormLength;

          NWS.$inputForm[0].setSelectionRange(start + NWS.offset, end + NWS.offset);
  },
  format: function(value){
    return value.replace(/\D/g, "").replace(/\B(?=(\d{3})+(?!\d))/g, NWS.char);
  }
}

$(document).ready(function(){

  $(document).on('keyup', '[name=price_from]', function(){
    NWS.ku('[name=price_from]');
  });

  $(document).on('keyup', '[name=price_to]', function(){
    NWS.ku('[name=price_to]');
  });
});