public void Load(IPersistStream stream)
        {
            _dbConn = new DbConnectionString();
            _dbConn.FromString((string)stream.Load("dbconn", String.Empty));
            _table   = (string)stream.Load("table", String.Empty);
            _idField = (string)stream.Load("idfield", String.Empty);
            _xField  = (string)stream.Load("xfield", String.Empty);
            _yField  = (string)stream.Load("yfield", String.Empty);


            string sr = (string)stream.Load("sref", String.Empty);

            if (String.IsNullOrEmpty(sr))
            {
                _sRef = null;
            }
            else
            {
                _sRef = new SpatialReference();
                _sRef.FromXmlString(sr);
            }
        }