ArcGIS Engine之统计

统计是地理信息系统基本功能之一，统计即为对某一图层的属性表的某一字段进行统计，得到其数目、最大值、最小值、众数等统计信息。

统计需要两个必要信息：要素、字段。

ArcGIS Engine中统计使用DataStatics类、IDataStatics接口

            ILayer pLayer = getLayerByName(comboBox1.Text);
            IFeatureLayer pFeaLyr=pLayer as IFeatureLayer;
            if(pFeaLyr==null) return;
            IFeatureCursor pCursor = pFeaLyr.Search(null,true);

            IDataStatistics pStatic = new DataStatisticsClass();
            pStatic.Field = comboBox2.Text;
            pStatic.Cursor = pCursor as ICursor;
            MessageBox.Show(""+pStatic.Statistics.Count);