SubsetNetworkEvaluators\ScaleSubsetEvaluator.vb
' Copyright 2012 ESRI ' ' All rights reserved under the copyright laws of the United States ' and applicable international laws, treaties, and conventions. ' ' You may freely redistribute and use this sample code, with or ' without modification, provided you include the original copyright ' notice and use restrictions. ' ' See the use restrictions. ' Imports Microsoft.VisualBasic Imports System Imports System.Collections.Generic Imports System.Text Imports System.Runtime.InteropServices Imports ESRI.ArcGIS.esriSystem Imports ESRI.ArcGIS.Geodatabase Namespace SubsetNetworkEvaluators ''' <summary> ''' The scale subset network evaluator is a custom network evaluator for modeling slowdown polygons ''' where traffic speeds are slowed down in only a particular subset of the network. In this ''' example the subset of network elements that are slowed down is determined based on the geometry ''' of graphic elements drawn in arc map, but it does not matter how the element subset is determined. ''' The elements that are not in the subset just return the non-scaled base attribute value. This could ''' be useful, for example, if certain low lying areas had a flash flood, or other localized congestion that ''' does not affect the network as a whole. The subset of elements to be scaled and the scale factor to ''' scale the base attribute by in the scale subset evaluator are network attribute parameters of the attribute ''' the evaluator is assigned to. ''' </summary> <ClassInterface(ClassInterfaceType.None), Guid("67cf8446-22a2-4baf-9c97-3c22a33cc0c7"), ProgId("SubsetNetworkEvaluators.ScaleSubsetEvaluator")> _ Public Class ScaleSubsetEvaluator : Implements INetworkEvaluator2, INetworkEvaluatorSetup #Region "Member Variables" Private m_networkDataset As INetworkDataset Private m_networkSource As INetworkSource Private m_networkAttribute As INetworkAttribute Private m_scaleFactor As Double = 1 Private m_thisNetworkAttributeID As Integer = -1 ' the ID for this attribute Private m_baseNetworkAttributeID As Integer = -1 ' the ID for the other attribute that should be scale (determined based on attribute name) Private m_countSourceEIDs As Integer = 0 ' number of EIDs to override for this source Private m_sourceEIDHashTable As Dictionary(Of Integer, Integer) ' the EIDs to override values for, by scaling, for this source #End Region #Region "INetworkEvaluator Members" Public ReadOnly Property CacheAttribute() As Boolean Implements INetworkEvaluator.CacheAttribute, INetworkEvaluator2.CacheAttribute ' CacheAttribute returns whether or not we want the network dataset to cache our evaluated attribute values during the network dataset build ' Since this is a dynamic evaluator, we will return false, so that our attribute values are dynamically queried at runtime Get Return False End Get End Property Public ReadOnly Property DisplayName() As String Implements INetworkEvaluator.DisplayName, INetworkEvaluator2.DisplayName Get Return "ScaleSubset" End Get End Property Public ReadOnly Property Name() As String Implements INetworkEvaluator.Name, INetworkEvaluator2.Name Get Return "SubsetNetworkEvaluators.ScaleSubset" End Get End Property #End Region #Region "INetworkEvaluator2 Members" Public Sub Refresh() Implements INetworkEvaluator2.Refresh ' This method is called internally during a solve operation immediately prior to performing the actual solve ' This gives us an opportunity to update our evaluator's internal state based on parameter values m_scaleFactor = 1 m_countSourceEIDs = 0 m_sourceEIDHashTable = New Dictionary(Of Integer, Integer)() Dim netAttribute2 As INetworkAttribute2 = TryCast(m_networkAttribute, INetworkAttribute2) Dim netAttributeParams As IArray = netAttribute2.Parameters ' Parameters: "ScaleSubset_Factor", "ScaleSubset_EIDs_<SourceName>" Dim prefix As String = BaseParameterName & "_" Dim paramScaleFactorName As String = prefix & "Factor" Dim paramEIDsName As String = prefix & "eids_" & m_networkSource.Name Dim nParamScaleFactor As Integer = SubsetHelper.FindParameter(netAttributeParams, paramScaleFactorName) Dim nParamEIDs As Integer = SubsetHelper.FindParameter(netAttributeParams, paramEIDsName) Dim value As Object Dim paramScaleFactor As INetworkAttributeParameter Dim paramEIDs As INetworkAttributeParameter If nParamScaleFactor >= 0 Then paramScaleFactor = TryCast(netAttributeParams.Element(nParamScaleFactor), INetworkAttributeParameter) value = paramScaleFactor.Value If Not value Is Nothing Then m_scaleFactor = CDbl(value) End If End If If nParamEIDs >= 0 Then paramEIDs = TryCast(netAttributeParams.Element(nParamEIDs), INetworkAttributeParameter) value = TryCast(paramEIDs.Value, Integer()) If Not value Is Nothing Then Dim eid As Integer Dim rgEIDs As Integer() rgEIDs = CType(value, Integer()) Dim lb As Integer = rgEIDs.GetLowerBound(0) Dim ub As Integer = rgEIDs.GetUpperBound(0) Dim i As Integer = lb Do While i <= ub m_countSourceEIDs += 1 eid = rgEIDs(i) m_sourceEIDHashTable.Add(eid, eid) i += 1 Loop End If End If End Sub Public ReadOnly Property RequiredFieldNames() As IStringArray Implements INetworkEvaluator2.RequiredFieldNames ' This custom evaluator does not require any field names Get Return Nothing End Get End Property #End Region #Region "INetworkEvaluatorSetup Members" Public ReadOnly Property CLSID() As UID Implements INetworkEvaluatorSetup.CLSID Get ' Create and return the GUID for this custom evaluator Dim uid As UID = New UIDClass() uid.Value = "{67cf8446-22a2-4baf-9c97-3c22a33cc0c7}" Return uid End Get End Property Public Property Data() As IPropertySet Implements INetworkEvaluatorSetup.Data ' The Data property is intended to make use of property sets to get/set the custom evaluator's properties using only one call to the evaluator object ' This custom evaluator does not make use of this property Get Return Nothing End Get Set(ByVal value As IPropertySet) End Set End Property Public ReadOnly Property DataHasEdits() As Boolean Implements INetworkEvaluatorSetup.DataHasEdits ' Since this custom evaluator does not make any data edits, return false Get Return False End Get End Property Public Sub Initialize(ByVal networkDataset As INetworkDataset, ByVal DataElement As IDENetworkDataset, ByVal netSource As INetworkSource, ByVal netAttribute As IEvaluatedNetworkAttribute) Implements INetworkEvaluatorSetup.Initialize ' Initialize is called once per session (ArcMap session, ArcCatalog session, etc.) to initialize the evaluator for an associated network dataset m_networkDataset = networkDataset m_networkSource = netSource m_networkAttribute = netAttribute m_thisNetworkAttributeID = netAttribute.ID m_baseNetworkAttributeID = -1 'The attribute name must begin with one or more non underscore characters followed by 'an underscore character and then the name of the base cost attribute. 'The underscore prior to the base attribute name should be the first underscore in the name. Dim thisAttributeName As String = netAttribute.Name Dim nPos As Integer = thisAttributeName.IndexOf("_"c) Dim nLastPos As Integer = thisAttributeName.Length - 1 Dim baseNetAttributeName As String Dim baseNetAttribute As INetworkAttribute = Nothing If nPos > 0 AndAlso nPos < nLastPos Then baseNetAttributeName = thisAttributeName.Remove(0, nPos + 1) Try baseNetAttribute = networkDataset.AttributeByName(baseNetAttributeName) Catch ex As COMException baseNetAttribute = Nothing Dim msg As String = String.Format("Base Attribute ({0}) not found. {1}.", baseNetAttributeName, ex.Message) System.Diagnostics.Trace.WriteLine(msg, "Scale Subset Network Evaluator") End Try If Not baseNetAttribute Is Nothing Then If baseNetAttribute.ID <> m_thisNetworkAttributeID Then m_baseNetworkAttributeID = baseNetAttribute.ID End If End If End If Refresh() End Sub Public Function QueryValue(ByVal Element As INetworkElement, ByVal Row As IRow) As Object Implements INetworkEvaluatorSetup.QueryValue If m_baseNetworkAttributeID < 0 Then Return -1 End If Dim value As Object = Element.AttributeValue(m_baseNetworkAttributeID) If value Is Nothing Then Return -1 End If Dim baseValue As Double = CDbl(value) If baseValue <= 0 OrElse m_scaleFactor = 1 OrElse m_countSourceEIDs <= 0 Then Return baseValue End If Dim isScaled As Boolean = False Dim eid As Integer = -1 If m_sourceEIDHashTable.TryGetValue(Element.EID, eid) Then isScaled = (eid > 0) End If Dim resultValue As Object = baseValue If isScaled Then If m_scaleFactor >= 0 Then resultValue = m_scaleFactor * baseValue Else resultValue = -1 End If End If Return resultValue End Function Public Function SupportsDefault(ByVal ElementType As esriNetworkElementType, ByVal netAttribute As IEvaluatedNetworkAttribute) As Boolean Implements INetworkEvaluatorSetup.SupportsDefault Return False End Function Public Function SupportsSource(ByVal netSource As INetworkSource, ByVal netAttribute As IEvaluatedNetworkAttribute) As Boolean Implements INetworkEvaluatorSetup.SupportsSource ' This custom evaluator supports cost attributes for all sources Return netAttribute.UsageType = esriNetworkAttributeUsageType.esriNAUTCost End Function Public Function ValidateDefault(ByVal ElementType As esriNetworkElementType, ByVal netAttribute As IEvaluatedNetworkAttribute, ByRef ErrorCode As Integer, ByRef ErrorDescription As String, ByRef errorAppendInfo As String) As Boolean Implements INetworkEvaluatorSetup.ValidateDefault If SupportsDefault(ElementType, netAttribute) Then ErrorCode = 0 ErrorDescription = String.Empty errorAppendInfo = String.Empty Return True Else ErrorCode = -1 ErrorDescription = String.Empty errorAppendInfo = String.Empty Return False End If End Function Public Function ValidateSource(ByVal datasetContainer As IDatasetContainer2, ByVal netSource As INetworkSource, ByVal netAttribute As IEvaluatedNetworkAttribute, ByRef ErrorCode As Integer, ByRef ErrorDescription As String, ByRef errorAppendInfo As String) As Boolean Implements INetworkEvaluatorSetup.ValidateSource If SupportsSource(netSource, netAttribute) Then ErrorCode = 0 ErrorDescription = String.Empty errorAppendInfo = String.Empty Return True Else ErrorCode = -1 ErrorDescription = String.Empty errorAppendInfo = String.Empty Return False End If End Function #End Region #Region "Static Members" Public Shared ReadOnly Property BaseParameterName() As String Get Return "ScaleSubset" End Get End Property Public Shared Sub RemoveScaleSubsetAttributes(ByVal deNet As IDENetworkDataset) Dim netAttributes As IArray = SubsetHelper.RemoveAttributesByPrefix(deNet.Attributes, BaseParameterName) deNet.Attributes = netAttributes End Sub Public Shared Function AddScaleSubsetAttributes(ByVal deNet As IDENetworkDataset) As List(Of IEvaluatedNetworkAttribute) Dim scaleSubsetAttributes As List(Of IEvaluatedNetworkAttribute) = New List(Of IEvaluatedNetworkAttribute)() Dim netAttributesArray As IArray = deNet.Attributes Dim baseIndexes As List(Of Integer) = SubsetHelper.FindAttributeIndexes(netAttributesArray, esriNetworkAttributeUsageType.esriNAUTCost, esriNetworkAttributeDataType.esriNADTDouble, True, False) Dim baseNetAttributes As List(Of INetworkAttribute2) = SubsetHelper.FindAttributes(netAttributesArray, baseIndexes) For Each baseNetAttribute As INetworkAttribute2 In baseNetAttributes scaleSubsetAttributes.Add(AddScaleSubsetAttribute(deNet, baseNetAttribute)) Next baseNetAttribute Return scaleSubsetAttributes End Function Public Shared Function AddScaleSubsetAttribute(ByVal deNet As IDENetworkDataset, ByVal baseNetAttribute As INetworkAttribute2) As IEvaluatedNetworkAttribute If baseNetAttribute Is Nothing Then Return Nothing End If If baseNetAttribute.UsageType <> esriNetworkAttributeUsageType.esriNAUTCost Then Return Nothing End If Dim netAttributes As IArray = deNet.Attributes Dim netAttribute As IEvaluatedNetworkAttribute = TryCast(New EvaluatedNetworkAttributeClass(), IEvaluatedNetworkAttribute) Dim netAttributeName As String = BaseParameterName netAttributeName &= "_" netAttributeName &= baseNetAttribute.Name netAttribute.Name = netAttributeName netAttribute.UsageType = baseNetAttribute.UsageType netAttribute.DataType = baseNetAttribute.DataType netAttribute.Units = baseNetAttribute.Units Dim allNetSources As List(Of INetworkSource) = SubsetHelper.GetSourceList(deNet.Sources) Dim netSources As List(Of INetworkSource) = SubsetHelper.GetSourceList(allNetSources, esriNetworkElementType.esriNETEdge) Dim netSourceNames As List(Of String) = SubsetHelper.GetSourceNames(netSources) ResetScaleSubsetParameters(CType(netAttribute, INetworkAttribute2), netSourceNames) Dim supportTurns As Boolean = deNet.SupportsTurns 'default evaluators SubsetHelper.SetDefaultEvaluator(netAttribute, 0, esriNetworkElementType.esriNETEdge) SubsetHelper.SetDefaultEvaluator(netAttribute, 0, esriNetworkElementType.esriNETJunction) If supportTurns Then SubsetHelper.SetDefaultEvaluator(netAttribute, 0, esriNetworkElementType.esriNETTurn) End If 'sourced evaluators For Each netSource As INetworkSource In netSources SubsetHelper.SetEvaluators(netAttribute, netSource, GetType(ScaleSubsetEvaluator)) Next netSource netAttributes.Add(netAttribute) deNet.Attributes = netAttributes Return netAttribute End Function Public Shared Sub ResetScaleSubsetParameters(ByVal netAttribute As INetworkAttribute2, ByVal netSourceNames As List(Of String)) Dim netParams As IArray = New ESRI.ArcGIS.esriSystem.ArrayClass() Dim netParam As INetworkAttributeParameter = Nothing Dim paramValue As Object = Nothing Dim paramName As String = "" netParam = New NetworkAttributeParameterClass() paramValue = 1 paramName = BaseParameterName paramName &= "_Factor" netParam.Name = paramName netParam.VarType = CInt(VarType.Double) netParam.Value = paramValue netParam.DefaultValue = paramValue netParams.Add(netParam) For Each netSourceName As String In netSourceNames netParam = New NetworkAttributeParameterClass() paramValue = Nothing paramName = BaseParameterName paramName &= "_eids_" paramName &= netSourceName netParam.Name = paramName netParam.VarType = CInt(VarType.Array Or VarType.Integer) netParam.Value = paramValue netParam.DefaultValue = paramValue netParams.Add(netParam) Next netSourceName 'does not preserve existing parameters if any netAttribute.Parameters = netParams End Sub #End Region End Class End Namespace