TopoFindRoute Method

Description

Creates a Named Seed object by route-finding between two Node Items within a dataset.

Syntax

Public Function TopoFindRoute( _
   ByVal seed As String, _
   ByVal idNode1 As Long, _
   ByVal idNode2 As Long, _
   ByVal nDataset As Long, _
   ByVal propertyName As String, _
   ByVal filter As String, _
   ByVal locusNoGo As String _
) As Integer

Parameters

seed

The name of the new Named Seed object.

 

idNode1

The start Node of the route.

 

idNode2

The end Node of the route.

 

nDataset

The serial number of the topological dataset. The serial number can be obtained from the Dataset property of an overlay, or from the GetDataset, FindExternalDataset or TopoGetNamedSeedDataset methods.

 

propertyName

The expression, or simple property, to use in the route finding calculation as the "cost" of a Link item. For example, using the simple property Length will find the shortest route, and using the expression "_length#/Speed#", provided each Link has a user-defined Speed# property, will find the quickest route. Any expression may be used, although if a string expression is used it must be a string representation of a numeric value. See Property Expression Syntax for details.

 

filter

Optionally specifies a named Filter which all Link Items must pass to be considered as part of the route.

 

locusNoGo

Optionally specifies a named Spatial Filter through which the route cannot pass.

Return Type

Remarks

Available: GEO ME MD OD SISpy

Group:

• Topology Methods 

Example

The named Spatial Filter used will normally have its testing mode set to exclude any Link Items which cross it, using a call similar to the following:

CreateLocusFromItem("SpatialFilter",SIS_GT_INTERSECT,SIS_GM_GEOMETRY)

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