ArcEngine创建缓冲区，并查询缓冲区内要素

电玩女神 2022-08-06 07:16 303阅读 0赞

实现功能：

1.获取鼠标选中的要素

2.对选中要素设置缓冲距离，在地图上显示缓冲区

3.进行缓冲区查询，获得缓冲区内的要素，并放入TreeList展示

/// <summary>
            /// 创建缓冲区
            /// </summary>
            private void CreateBuffer()
            {
                ITopologicalOperator pTopo = null;
                IElement pElement = null;
                IGeometry pBuffer = null;
                IGeometry pGeo = null;
                ISelection pSelection = null;
                IEnumFeatureSetup pEnumFeatureSetup = null;
                IEnumFeature pEnumFeature = null;
                IFillSymbol pFillSymbol = null;
                IRgbColor pRgbColor = null;
    
                IFeature pFea = null;
                IFeature pFeature = null;
                IFeatureLayer pFeaLayer = null;
                IFeatureClass pFeaClass = null;
                IFeatureCursor pFeaCursor = null;
    
                ISpatialFilter pSpatialfilter = null;
    
                try
                {
                    if (m_pMap != null)
                    {
                        (m_pMap as IGraphicsContainer).DeleteAllElements();
                    }
    
                        获得选中要素
                    pSelection = m_pMap.FeatureSelection;
                    pEnumFeatureSetup = pSelection as IEnumFeatureSetup;
                    pEnumFeatureSetup.AllFields = true;
    
                    pEnumFeature = pEnumFeatureSetup as IEnumFeature;
                    pEnumFeature.Reset();
                    pFea = pEnumFeature.Next();
    
                        遍历选中要素
                    while (pFea != null)
                    {
                        pGeo = pFea.ShapeCopy;
                        pTopo = pGeo as ITopologicalOperator;
                        pBuffer = pTopo.Buffer(m_dDistance);
    
                        pElement = new PolygonElementClass();
                        pElement.Geometry = pBuffer;
    
                            设置缓冲区颜色
                        pFillSymbol = new SimpleFillSymbolClass();
                        pRgbColor = new RgbColorClass();
                        pRgbColor.Red = 255;
                        pRgbColor.Green = 255;
                        pRgbColor.Blue = 153;
                        pRgbColor.Transparency = 1;
                        pFillSymbol.Color = pRgbColor;
                        (pElement as IFillShapeElement).Symbol = pFillSymbol;
                        (m_pMap as IGraphicsContainer).AddElement(pElement, 0);
    
                            设置空间过滤器
                        pSpatialfilter = new SpatialFilterClass();
                        pSpatialfilter.Geometry = pBuffer;
    
                            遍历图层
                        for (int i = 0; i < m_pMap.LayerCount; i++)
                        {
                            pFeaLayer = m_pMap.get_Layer(i) as IFeatureLayer;
                            pFeaClass = pFeaLayer.FeatureClass;
    
                            switch (pFeaClass.ShapeType)
                            {
                                case esriGeometryType.esriGeometryPoint:
                                    {
                                        pSpatialfilter.SpatialRel = esriSpatialRelEnum.esriSpatialRelContains;
                                        break;
                                    }
                                case esriGeometryType.esriGeometryPolyline:
                                    {
                                        pSpatialfilter.SpatialRel = esriSpatialRelEnum.esriSpatialRelContains;
                                        break;
                                    }
                                case esriGeometryType.esriGeometryPolygon:
                                    {
                                        pSpatialfilter.SpatialRel = esriSpatialRelEnum.esriSpatialRelContains;
                                        break;
                                    }
                            }
    
                            pSpatialfilter.GeometryField = pFeaClass.ShapeFieldName;
                            pFeaCursor = pFeaClass.Search(pSpatialfilter, false);
                            pFeature = pFeaCursor.NextFeature();
    
                            TreeListNode tlNode = null;
    
                                查询到的要素添加到TreeList
                            while (pFeature != null)
                            {
                                    添加图层节点到TreeList
                                bool bIsContainLayer = false;
                                foreach (TreeListNode node in tlResult.Nodes)
                                {
                                    if (node.GetDisplayText(0).Equals(pFeaLayer.Name))
                                    {
                                        tlNode = node;
                                        bIsContainLayer = true;
                                        break;
                                    }
                                }
                                if (!bIsContainLayer)
                                {
                                    tlNode = tlResult.AppendNode(new object[] { pFeaLayer.Name }, null);
                                }
    
                                    添加要素到图层节点下
                                bool bIsAdd = false;
                                foreach (TreeListNode childnode in tlNode.Nodes)
                                {
                                    if (childnode.GetDisplayText(0).Equals(pFeature.OID.ToString()))
                                    {
                                        bIsAdd = true;
                                        break;
                                    }
                                }
                                if (!bIsAdd)
                                {
                                    tlResult.AppendNode(new object[] { pFeature.OID, GtMap.GxAEHelper.Feature.GetValue(pFeature, "NAME") }, tlNode);
                                }
    
                                pFeature = pFeaCursor.NextFeature();
                            }
                        }
    
                        pFea = pEnumFeature.Next();
                    }
    
                    IActiveView pActiveView = m_pMap as IActiveView;
                    pActiveView.Refresh();
    
                }
                catch (Exception ex)
                {
    
                }
            }