code: public KeyField getKeyField(int iKeyFieldSeq)
      {
          if (iKeyFieldSeq >= m_vKeyFieldList.size())
              return null;
          return (KeyField)m_vKeyFieldList.elementAt(iKeyFieldSeq);
      }
docs: Get this Key Field.
  @param iKeyFieldSeq The position of this keyfield in the key area.
  @return The key field.