n checkPayment()
  {
    if (!radioChecked('payment'))
    {
      alert(pls_select_payment);
      return false;
    }
    return true;
  }

  /**
   * 返回某 radio 是否被选中一个
   * @param string radioName
   */
  function radioChecked(radioName)
  {
    var eles = document.forms['theForm'].elements;

    for (var i = 0; i < eles.length; i++)
    {
      if (eles[i].name == radioName && eles[i].checked)
      {
        return true;
      }
    }
    return false;
  }

  /**
   * 按用户编�