function trim(str) {
  return str.replace(/^\s+|\s+$/g, '')
}

function is_empty(s) {
  return ((s == null) || (s.length == 0));
}

function limitText(limitField,limitNum) {
  if (limitField.value.length > limitNum) {
    limitField.value = trim(limitField.value).substring(0,limitNum);
  }else
  {
    limitField.value = limitField.value;
  }
}