GIS应用开发PGIS2015-chap.9空间查询与空间分析讲述.ppt

private void cbxPolygonLayers_SelectedIndexChanged(object sender, EventArgs e) { string strSelectedLayer = cbxPolygonLayers.SelectedItem.ToString(); currentLayer = GetFeatureLayer(strSelectedLayer); SetCurrentLayerSelectable(strSelectedLayer); } private void btnSelectOnePolygon_Click(object sender, EventArgs e) { m_map.ClearSelection(); SetSelectToolAsCurrentTool(); } private void btnQuery_Click(object sender, EventArgs e) { … IFeatureSelection featureSelection = currentLayer as IFeatureSelection; ISelectionSet selectionSet = featureSelection.SelectionSet; IEnumIDs selectedIDs = selectionSet.IDs; selectedIDs.Reset(); int selectedID = selectedIDs.Next(); IFeature baseFeature = currentLayer.FeatureClass.GetFeature(selectedID); if (baseFeature != null) { IGeometry baseGeom = baseFeature.Shape; ISpatialFilter pSFilter = new SpatialFilterClass(); pSFilter.Geometry = baseGeom; pSFilter.GeometryField = Shape; pSFilter.SpatialRel = esriSpatialRelEnum.esriSpatialRelTouches; featureSelection.SelectFeatures (pSFilter, esriSelectionResultEnum.esriSelectionResultNew, false); } m_activeView.PartialRefresh(esriViewDrawPhase.esriViewGeoSelection, null, m_activeView.Extent); …… } 9.7 缓冲区分析 根据选择图层创建缓冲区，然后将选择的叠置图层与缓冲区图层进行叠置分析。 SpatialAnalysis.BufferAnalysis : Form 缓冲区分析的实现主要包括两个步骤：缓冲区的创建和叠置分析。 缓冲区的创建使用Buffer地理处理工具，其语法如下： Buffer_analysis (in_features, out_feature_class, buffer_distance_or_field, line_side, line_end_type, dissolve_option, dissolve_field) 叠置图层与缓冲区图层的叠置分析，这里仅考虑求交叠置，并使用Intersect地理处理工具，其语法如下： Intersect_analysis (in_features, out_feature_class, join_attributes, cluster_tolerance, output_type) 实现的主要代码 private void btnBufferAnalysis_Click(object sender, EventArgs e) { Geoprocessor gp =