拓朴分析之面中检查有几个点（查只有一个点 作为标注）

如题，查找面中　点的个数，先看看　IQueryFilter　ISpatialFilter吧

ISpatialFilter is a QueryFilter that includes both spatial and attribute constraints. 

多用于空间查询

IQueryFilter filters data based on an attribute query

多用于简间的属性查询

            // 获取选中的点要素类和面要素类　dstPointLayer是自定义控件，选择图层就能得到要素图层
         IFeatureClass pPointFtrCls = (dstPointLayer.SelectedLayer as IFeatureLayer).FeatureClass;
            IFeatureClass pAreaFtrCls = (dstAreaLayer.SelectedLayer as IFeatureLayer).FeatureClass;

            // 获取面要素类的工作空间，建立不符合条件的要素OID的选择集。
         IWorkspace pWorkspace = (dstPointLayer.SelectedLayer as IDataset).Workspace;
            IQueryFilter pQueryFiler = new QueryFilterClass();
            if (pAreaFtrCls.Fields.FieldCount > 0)
            {
                pQueryFiler.WhereClause = pAreaFtrCls.Fields.get_Field(0).Name + "=-1";
            }
            else
                pQueryFiler.WhereClause = "1=0";
            ISelectionSet pOIDSet = pAreaFtrCls.Select(pQueryFiler, esriSelectionType.esriSelectionTypeIDSet, esriSelectionOption.esriSelectionOptionNormal, pWorkspace);

            // 用于过滤获取当前面范围内的所有点
         ISpatialFilter pSpatialFilter = null;

            ISpatialFilter sf = new SpatialFilterClass();


      　　 if (chkViewExtent.Checked)
            {
                IActiveView tav = Winsharp.BaseClass.AppConfigInfo.Framework.Application.FocusMap as IActiveView;
                IGeometry tent = tav.Extent;
                sf.Geometry = tent;
                sf.GeometryField = "Shape";
                sf.SpatialRel = esriSpatialRelEnum.esriSpatialRelIntersects;
                sf.WhereClause = "";
            }

            // 获取所有面要素，逐个检查其范围内的点数。
            int pCount = pAreaFtrCls.FeatureCount(sf);
            IFeatureCursor pAreaCursor = null;
            ICursor tmpCursor;
            if (chkSelection.Checked)
            {
                IFeatureSelection pfselection = (dstAreaLayer.SelectedLayer as IFeatureLayer) as IFeatureSelection;
                pfselection.SelectionSet.Search(sf, false, out tmpCursor);
                pAreaCursor = tmpCursor as IFeatureCursor;
                pCount = pfselection.SelectionSet.Count;
            }
            else
            {
                pAreaCursor = pAreaFtrCls.Search(sf, false);
            }
            IFeature pAreaFeature = pAreaCursor.NextFeature();



            while (pAreaFeature != null)
            {
                // 若中止操作，则退出函数。
                if (this.m_HasCancel)
                    return;

                // 定义空间过滤条件，过滤全包含在面之内的点。
                pSpatialFilter = new SpatialFilterClass();
                pSpatialFilter.Geometry = pAreaFeature.ShapeCopy;
                pSpatialFilter.SpatialRel = esriSpatialRelEnum.esriSpatialRelContains;
                pSpatialFilter.WhereClause = "";
                pSpatialFilter.GeometryField = pPointFtrCls.ShapeFieldName;

                // 获取全包含在面之内的点的数目。若点数不为1，则记录面的OID
                pCount = pPointFtrCls.FeatureCount(pSpatialFilter);
              
                if (pCount != 1)
                {
                   pOIDSet.Add(pAreaFeature.OID);
                }

                // 移动指针，获取下一个面要素，同时修改进度条。
                pAreaFeature = pAreaCursor.NextFeature();
                this.m_Helper.Position++;
                if (m_HasCancel)
                    break;
            }