请教高手数据集异常问题，layer.GeoDataset() = gds菜鸟提问！

<P>Dim layer As New MapObjects2.MapLayer() ' 声明一个图层对象<BR>Dim gds As MapObjects2.GeoDataset gds = _environment.m_db.FindGeoDataset(_environment.m_layerInfos(i).szFileName)<BR> layer.GeoDataset() = gds  ' 设置图层的GeoDataset属性</P>
<P>帮我看看啊！程序在编译时没错，为什么执行就指示这句出错了layer.GeoDataset() = gds  出现异常！能怎么解决啊！</P><img src="images/post/smile/dvbbs/em12.gif" />