删除拓扑的代码如下：
``` ITopologyProperties pTopologyProp = (ITopologyProperties)_pTopology;
IEnumFeatureClass pEnumFeatureClass = pTopologyProp.Classes;
pEnumFeatureClass.Reset();
IFeatureClass pFeatureClass = null;
while ((pFeatureClass = pEnumFeatureClass.Next()) != null)
{
IClass pClass = pFeatureClass as IClass;
_pTopology.RemoveClass(pClass);
}
_pDataset.Delete();//拓扑要素集
拓扑是在停止编辑的情况下删除的，可是删除后，创建拓扑的那个要素层就不能编辑要素了，提示是找不到T_1_DrityArea表，T_1_DrityArea应该是脏区的表，请大神赐教！！！！
