ArcGIS Pro SDK （八）地理数据库 8 拓扑

ArcGIS Pro SDK （八）地理数据库 8 拓扑

环境：Visual Studio 2022 + .NET6 + ArcGIS Pro SDK 3.0

1 开放拓扑和进程定义

public void OpenTopologyAndProcessDefinition()
{// 从文件地理数据库中打开拓扑并处理拓扑定义。using (Geodatabase geodatabase = new Geodatabase(new FileGeodatabaseConnectionPath(new Uri(@"C:\TestData\GrandTeton.gdb"))))using (Topology topology = geodatabase.OpenDataset<Topology>("Backcountry_Topology")){ProcessDefinition(geodatabase, topology);}// 打开要素服务拓扑并处理拓扑定义。const string TOPOLOGY_LAYER_ID = "0";using (Geodatabase geodatabase = new Geodatabase(new ServiceConnectionProperties(new Uri("https://sdkexamples.esri.com/server/rest/services/GrandTeton/FeatureServer"))))using (Topology topology = geodatabase.OpenDataset<Topology>(TOPOLOGY_LAYER_ID)){ProcessDefinition(geodatabase, topology);}
}private void ProcessDefinition(Geodatabase geodatabase, Topology topology)
{// 类似于Core.Data API中其余Definition对象，打开数据集的定义有两种方式 -- 通过拓扑数据集本身或通过地理数据库。using (TopologyDefinition definitionViaTopology = topology.GetDefinition()){OutputDefinition(geodatabase, definitionViaTopology);}using (TopologyDefinition definitionViaGeodatabase = geodatabase.GetDefinition<TopologyDefinition>("Backcountry_Topology")){OutputDefinition(geodatabase, definitionViaGeodatabase);}
}private void OutputDefinition(Geodatabase geodatabase, TopologyDefinition topologyDefinition)
{Console.WriteLine($"拓扑聚类容差 => {topologyDefinition.GetClusterTolerance()}");Console.WriteLine($"拓扑Z值聚类容差 => {topologyDefinition.GetZClusterTolerance()}");IReadOnlyList<string> featureClassNames = topologyDefinition.GetFeatureClassNames();Console.WriteLine($"有 {featureClassNames.Count} 个要素类参与了拓扑:");foreach (string name in featureClassNames){// 打开每个参与拓扑的要素类。using (FeatureClass featureClass = geodatabase.OpenDataset<FeatureClass>(name))using (FeatureClassDefinition featureClassDefinition = featureClass.GetDefinition()){Console.WriteLine($"\t{featureClass.GetName()} ({featureClassDefinition.GetShapeType()})");}}
}

2 获取拓扑规则

using (TopologyDefinition topologyDefinition = topology.GetDefinition())
{IReadOnlyList<TopologyRule> rules = topologyDefinition.GetRules();Console.WriteLine($"拓扑定义了 {rules.Count} 条拓扑规则:");Console.WriteLine("ID \t 源类 \t 源子类 \t 目标类 \t 目标子类 \t 规则类型");foreach (TopologyRule rule in rules){Console.Write($"{rule.ID}");Console.Write(!String.IsNullOrEmpty(rule.OriginClass) ? $"\t{rule.OriginClass}" : "\t\"\"");Console.Write(rule.OriginSubtype != null ? $"\t{rule.OriginSubtype.GetName()}" : "\t\"\"");Console.Write(!String.IsNullOrEmpty(rule.DestinationClass) ? $"\t{rule.DestinationClass}" : "\t\"\"");Console.Write(rule.DestinationSubtype != null ? $"\t{rule.DestinationSubtype.GetName()}" : "\t\"\"");Console.Write($"\t{rule.RuleType}");Console.WriteLine();}
}

3 验证拓扑

public void ValidateTopology()
{using (Geodatabase geodatabase = new Geodatabase(new FileGeodatabaseConnectionPath(new Uri(@"C:\TestData\GrandTeton.gdb"))))using (Topology topology = geodatabase.OpenDataset<Topology>("Backcountry_Topology")){// 如果拓扑当前没有脏区域，调用Validate()将返回一个空的包络线。ValidationResult result = topology.Validate(new ValidationDescription(topology.GetExtent()));Console.WriteLine($"在未编辑的拓扑上验证后的'受影响区域' => {result.AffectedArea.ToJson()}");// 现在创建一个故意违反“PointProperlyInsideArea”拓扑规则的要素。这个动作将创建脏区域。Feature newFeature = null;try{// 获取Campsite要素类中ObjectID为2的要素。然后从这个要素稍微修改后创建一个新的几何体，并用它创建一个新的要素。using (Feature featureViaCampsites2 = GetFeature(geodatabase, "Campsites", 2)){Geometry currentGeometry = featureViaCampsites2.GetShape();Geometry newGeometry = GeometryEngine.Instance.Move(currentGeometry, (currentGeometry.Extent.XMax / 8),(currentGeometry.Extent.YMax / 8));using (FeatureClass campsitesFeatureClass = featureViaCampsites2.GetTable())using (FeatureClassDefinition definition = campsitesFeatureClass.GetDefinition())using (RowBuffer rowBuffer = campsitesFeatureClass.CreateRowBuffer()){rowBuffer[definition.GetShapeField()] = newGeometry;geodatabase.ApplyEdits(() =>{newFeature = campsitesFeatureClass.CreateRow(rowBuffer);});}}// 在'Campsites'参与要素类中创建新要素后，拓扑的状态应为“未分析”，因为尚未验证。Console.WriteLine($"应用编辑后拓扑状态 => {topology.GetState()}");// 现在验证拓扑。结果包络线对应于脏区域。result = topology.Validate(new ValidationDescription(topology.GetExtent()));Console.WriteLine($"在刚编辑后验证的拓扑上的'受影响区域' => {result.AffectedArea.ToJson()}");// 在Validate()之后，拓扑的状态应为“有错误的分析”，因为拓扑当前存在错误。Console.WriteLine($"验证拓扑后的拓扑状态 => {topology.GetState()}");// 如果没有脏区域，则结果包络线应为空。result = topology.Validate(new ValidationDescription(topology.GetExtent()));Console.WriteLine($"在刚验证过的拓扑上的'受影响区域' => {result.AffectedArea.ToJson()}");}finally{if (newFeature != null){geodatabase.ApplyEdits(() =>{newFeature.Delete();});newFeature.Dispose();}}// 删除新创建的要素后再次验证。topology.Validate(new ValidationDescription(topology.GetExtent()));}
}private Feature GetFeature(Geodatabase geodatabase, string featureClassName, long objectID)
{using (FeatureClass featureClass = geodatabase.OpenDataset<FeatureClass>(featureClassName)){QueryFilter queryFilter = new QueryFilter(){ObjectIDs = new List<long>() { objectID }};using (RowCursor cursor = featureClass.Search(queryFilter)){System.Diagnostics.Debug.Assert(cursor.MoveNext());return (Feature)cursor.Current;}}
}

4 获取拓扑错误

// 获取当前与拓扑相关的所有错误和异常。IReadOnlyList<TopologyError> allErrorsAndExceptions = topology.GetErrors(new ErrorDescription(topology.GetExtent()));
Console.WriteLine($"错误和异常数目 => {allErrorsAndExceptions.Count}");Console.WriteLine("源类名称 \t 源对象ID \t 目标类名称 \t 目标对象ID \t 规则类型 \t 是否异常 \t 几何类型 \t 几何宽度 & 高度 \t 规则ID \t");foreach (TopologyError error in allErrorsAndExceptions)
{Console.WriteLine($"'{error.OriginClassName}' \t {error.OriginObjectID} \t '{error.DestinationClassName}' \t " +$"{error.DestinationObjectID} \t {error.RuleType} \t {error.IsException} \t {error.Shape.GeometryType} \t " +$"{error.Shape.Extent.Width},{error.Shape.Extent.Height} \t {error.RuleID}");
}

5 标记和不标记为错误

// 获取所有由于违反“PointProperlyInsideArea”拓扑规则而引起的错误。using (TopologyDefinition topologyDefinition = topology.GetDefinition())
{TopologyRule pointProperlyInsideAreaRule = topologyDefinition.GetRules().First(rule => rule.RuleType == TopologyRuleType.PointProperlyInsideArea);ErrorDescription errorDescription = new ErrorDescription(topology.GetExtent()){TopologyRule = pointProperlyInsideAreaRule};IReadOnlyList<TopologyError> errorsDueToViolatingPointProperlyInsideAreaRule = topology.GetErrors(errorDescription);Console.WriteLine($"有 {errorsDueToViolatingPointProperlyInsideAreaRule.Count} 个要素违反了'PointProperlyInsideArea'拓扑规则.");// 将违反“PointProperlyInsideArea”拓扑规则的所有错误标记为异常。foreach (TopologyError error in errorsDueToViolatingPointProperlyInsideAreaRule){topology.MarkAsException(error);}// 现在验证所有违反“PointProperlyInsideArea”拓扑规则的错误是否确实已标记为异常。//// 默认情况下，ErrorDescription初始化为ErrorType.ErrorAndException。在这里我们想要ErrorType.ErrorOnly。errorDescription = new ErrorDescription(topology.GetExtent()){ErrorType = ErrorType.ErrorOnly,TopologyRule = pointProperlyInsideAreaRule};IReadOnlyList<TopologyError> errorsAfterMarkedAsExceptions = topology.GetErrors(errorDescription);Console.WriteLine($"在将所有错误标记为异常后，有 {errorsAfterMarkedAsExceptions.Count} 个要素违反了'PointProperlyInsideArea'拓扑规则.");// 最后，通过取消标记为异常将所有异常重置为错误。foreach (TopologyError error in errorsDueToViolatingPointProperlyInsideAreaRule){topology.UnmarkAsException(error);}IReadOnlyList<TopologyError> errorsAfterUnmarkedAsExceptions = topology.GetErrors(errorDescription);Console.WriteLine($"在将所有异常重置为错误后，有 {errorsAfterUnmarkedAsExceptions.Count} 个要素违反了'PointProperlyInsideArea'拓扑规则.");
}

6 探索拓扑图

public void ExploreTopologyGraph()
{using (Geodatabase geodatabase = new Geodatabase(new FileGeodatabaseConnectionPath(new Uri(@"C:\TestData\GrandTeton.gdb"))))using (Topology topology = geodatabase.OpenDataset<Topology>("Backcountry_Topology")){// 使用拓扑数据集的范围构建拓扑图。topology.BuildGraph(topology.GetExtent(),(topologyGraph) =>{using (Feature campsites12 = GetFeature(geodatabase, "Campsites", 12)){IReadOnlyList<TopologyNode> topologyNodesViaCampsites12 = topologyGraph.GetNodes(campsites12);TopologyNode topologyNodeViaCampsites12 = topologyNodesViaCampsites12[0];IReadOnlyList<TopologyEdge> allEdgesConnectedToNodeViaCampsites12 = topologyNodeViaCampsites12.GetEdges();IReadOnlyList<TopologyEdge> allEdgesConnectedToNodeViaCampsites12CounterClockwise = topologyNodeViaCampsites12.GetEdges(false);System.Diagnostics.Debug.Assert(allEdgesConnectedToNodeViaCampsites12.Count == allEdgesConnectedToNodeViaCampsites12CounterClockwise.Count);foreach (TopologyEdge edgeConnectedToNodeViaCampsites12 in allEdgesConnectedToNodeViaCampsites12){TopologyNode fromNode = edgeConnectedToNodeViaCampsites12.GetFromNode();TopologyNode toNode = edgeConnectedToNodeViaCampsites12.GetToNode();bool fromNodeIsTheSameAsTopologyNodeViaCampsites12 = (fromNode == topologyNodeViaCampsites12);bool toNodeIsTheSameAsTopologyNodeViaCampsites12 = (toNode == topologyNodeViaCampsites12);System.Diagnostics.Debug.Assert(fromNodeIsTheSameAsTopologyNodeViaCampsites12 || toNodeIsTheSameAsTopologyNodeViaCampsites12,"连接到'topologyNodeViaCampsites12'的每个边的FromNode或ToNode应与'topologyNodeViaCampsites12'本身相同。");IReadOnlyList<FeatureInfo> leftParentFeaturesBoundedByEdge = edgeConnectedToNodeViaCampsites12.GetLeftParentFeatures();foreach (FeatureInfo featureInfo in leftParentFeaturesBoundedByEdge){System.Diagnostics.Debug.Assert(!String.IsNullOrEmpty(featureInfo.FeatureClassName));System.Diagnostics.Debug.Assert(featureInfo.ObjectID > 0);EnsureShapeIsNotEmpty(featureInfo);}IReadOnlyList<FeatureInfo> leftParentFeaturesNotBoundedByEdge = edgeConnectedToNodeViaCampsites12.GetLeftParentFeatures(false);foreach (FeatureInfo featureInfo in leftParentFeaturesNotBoundedByEdge){System.Diagnostics.Debug.Assert(!String.IsNullOrEmpty(featureInfo.FeatureClassName));System.Diagnostics.Debug.Assert(featureInfo.ObjectID > 0);EnsureShapeIsNotEmpty(featureInfo);}IReadOnlyList<FeatureInfo> rightParentFeaturesBoundedByEdge = edgeConnectedToNodeViaCampsites12.GetRightParentFeatures();foreach (FeatureInfo featureInfo in rightParentFeaturesBoundedByEdge){System.Diagnostics.Debug.Assert(!String.IsNullOrEmpty(featureInfo.FeatureClassName));System.Diagnostics.Debug.Assert(featureInfo.ObjectID > 0);EnsureShapeIsNotEmpty(featureInfo);}IReadOnlyList<FeatureInfo> rightParentFeaturesNotBoundedByEdge = edgeConnectedToNodeViaCampsites12.GetRightParentFeatures(false);foreach (FeatureInfo featureInfo in rightParentFeaturesNotBoundedByEdge){System.Diagnostics.Debug.Assert(!String.IsNullOrEmpty(featureInfo.FeatureClassName));System.Diagnostics.Debug.Assert(featureInfo.ObjectID > 0);EnsureShapeIsNotEmpty(featureInfo);}}}});}
}private void EnsureShapeIsNotEmpty(FeatureInfo featureInfo)
{using (Feature feature = featureInfo.GetFeature()){System.Diagnostics.Debug.Assert(!feature.GetShape().IsEmpty, "要素的形状不应为空。");}
}

7 找到最近的元素

public void FindClosestElement()
{using (Geodatabase geodatabase = new Geodatabase(new FileGeodatabaseConnectionPath(new Uri(@"C:\TestData\GrandTeton.gdb"))))using (Topology topology = geodatabase.OpenDataset<Topology>("Backcountry_Topology")){// 使用拓扑数据集的范围构建拓扑图。topology.BuildGraph(topology.GetExtent(), (topologyGraph) =>{MapPoint queryPointViaCampsites12 = null;using (Feature campsites12 = GetFeature(geodatabase, "Campsites", 12)){queryPointViaCampsites12 = campsites12.GetShape() as MapPoint;}double searchRadius = 1.0;TopologyElement topologyElementViaCampsites12 = topologyGraph.FindClosestElement<TopologyElement>(queryPointViaCampsites12, searchRadius);System.Diagnostics.Debug.Assert(topologyElementViaCampsites12 != null, "在searchRadius范围内应该有一个与'queryPointViaCampsites12'对应的拓扑元素.");IReadOnlyList<FeatureInfo> parentFeatures = topologyElementViaCampsites12.GetParentFeatures();Console.WriteLine("生成'topologyElementViaCampsites12'的父要素:");foreach (FeatureInfo parentFeature in parentFeatures){Console.WriteLine($"\t{parentFeature.FeatureClassName}; OID: {parentFeature.ObjectID}");}TopologyNode topologyNodeViaCampsites12 = topologyGraph.FindClosestElement<TopologyNode>(queryPointViaCampsites12, searchRadius);if (topologyNodeViaCampsites12 != null){// 在searchRadius单位内存在一个最近的TopologyNode。}TopologyEdge topologyEdgeViaCampsites12 = topologyGraph.FindClosestElement<TopologyEdge>(queryPointViaCampsites12, searchRadius);if (topologyEdgeViaCampsites12 != null){// 在searchRadius单位内存在一个最近的TopologyEdge。}});}
}