AE按行政区范围加载图层数据(转载)

大家可能在平时开发中可能会遇到按行政区加载图层数据的需求，比方说整个国土资源部有某一类型专题数据有若干图层，每个图层数据的范围是整个中国，这时国土资源部开发一套系统可能有这个需求，每个省只能加载本省的数据。以下函数即为按按行政区范围创建行政区范围的图层。
比方说我想获取河南省的数据只需传入行政区图层中河南省图元的Geometry即可。另外如果如果遇到行政区层必须用 esriSpatialRelEnum.esriSpatialRelContains这个参数，否则行政区这个图层就不能只获取河南这个省份，它会把河南省的周围省份，河北，湖北，安徽，陕西，山东，山西等省份的图元也添加创建到新图层。
    

   /// <summary>
        /// 按行政区范围创建行政区范围的图层
        /// </summary>
        /// <param name="pFeatureLayer">源数据图层</param>
        /// <param name="pGeometry">行政区范围</param>
        /// <param name="bXZQ">图层是否为行政区</param>
        /// <returns>新创建的图层</returns>
        private IFeatureLayer  GetSelectionLayer(IFeatureLayer pFeatureLayer, IGeometry pGeometry,bool bXZQ)
        {
            try
            {
                if (pFeatureLayer != null && pGeometry != null)
                {
                    IQueryFilter pQueryFilter;
                    ISpatialFilter pSpatialFilter = new SpatialFilterClass();
                    IFeatureSelection pFeatureSelection = pFeatureLayer as IFeatureSelection;
                    pSpatialFilter.GeometryField = pFeatureLayer.FeatureClass.ShapeFieldName;
                    pFeatureSelection.Clear();                  
                    if (!bXZQ)
                    {
                        pSpatialFilter.Geometry = pGeometry;                      
                        pSpatialFilter.SpatialRel = esriSpatialRelEnum.esriSpatialRelIntersects;
                        pQueryFilter = pSpatialFilter;                       
                        pFeatureSelection.SelectFeatures(pQueryFilter, esriSelectionResultEnum.esriSelectionResultNew, false);
                    }
                    else
                    {
                        pSpatialFilter.SpatialRel = esriSpatialRelEnum.esriSpatialRelContains;
                        pQueryFilter = pSpatialFilter;                       
                        if(pGeometry is IGeometryCollection)
                        {
                            for (int i = 0; i < (pGeometry as IGeometryCollection).GeometryCount; i++)
                            {
                                pSpatialFilter.Geometry = (pGeometry as IGeometryCollection).get_Geometry(i); 
                                pFeatureSelection.SelectFeatures(pQueryFilter, esriSelectionResultEnum.esriSelectionResultAdd, false);
                            }
                        }
                    }                 
                    IFeatureLayerDefinition pFLDefinition = pFeatureLayer as IFeatureLayerDefinition;
                    IFeatureLayer pNewFeatureLayer = pFLDefinition.CreateSelectionLayer(pFeatureLayer.Name ,true, null, null);
                    pNewFeatureLayer.MaximumScale = pFeatureLayer.MaximumScale;
                    pNewFeatureLayer.MinimumScale = pFeatureLayer.MinimumScale;
                    pNewFeatureLayer.Selectable = pFeatureLayer.Selectable;
                    pNewFeatureLayer.Visible = pFeatureLayer.Visible;
                    pNewFeatureLayer.ScaleSymbols = pFeatureLayer.ScaleSymbols;
                    return pNewFeatureLayer;
                }
                else
                {
                    return null;
                }
            }
            catch (Exception Err)
            {
                MessageBox.Show(Err.Message, "获取SelectionLayer", MessageBoxButtons.OK, MessageBoxIcon.Information);
                return null;
            }
        }
        
    }

原文地址:http://bbs.esrichina-bj.cn/ESRI/viewthread.php?tid=34165&extra=&page=1