function getRadioValue (radioButtonOrGroup) {
  var buttonsLength = radioButtonOrGroup.length;
  if (buttonsLength) { // group
    for (var b = 0; b < buttonsLength; b++)
      if (radioButtonOrGroup[b].checked)
        return radioButtonOrGroup[b].value;
  }
  else if (radioButtonOrGroup.checked)
    return radioButtonOrGroup.value;
  return null;
}

function validEmail(str){
	var filter=/^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i
	return filter.test(str);
}