Creates topo elements from all topology feature classes covering the specified map extent.
[Visual Basic .NET] Public Sub Build ( _ ByVal Extent As IEnvelope, _ ByVal preserveSelection As Boolean _ )
[C#] public void Build ( IEnvelope Extent, bool preserveSelection );
[C++]
HRESULT Build(
IEnvelope* Extent,
VARIANT_BOOL preserveSelection
);
[C++]Parameters
ExtentExtent is a parameter of type IEnvelope
preserveSelection preserveSelection is a parameter of type VARIANT_BOOL
Product Availability
Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.
Description
Use the ITopologyGraph::Build method to construct the Topology Elements (TopologyNodes and TopologyEdges). Once "Build" is performed the Topology Elements are cached in memory and can be used. The elements have to be built before they can be used with other methods.
[C#]
bool BuildTopoGraph(IGeometry buildGeom, ITopologyGraph topoGraph, bool
keepSelection)
{
if (buildGeom == null || topoGraph == null)
return false;
switch (buildGeom.GeometryType)
{
case esriGeometryType.esriGeometryPolygon:
{
ITopologyGraph4 topoGraph4 = topoGraph as ITopologyGraph4;
topoGraph4.BuildFromPolygon((IPolygon)buildGeom, keepSelection);
return true;
}
case esriGeometryType.esriGeometryEnvelope:
{
topoGraph.Build((IEnvelope)buildGeom, keepSelection);
return true;
}
default:
return false;
}
}[Visual Basic .NET]
Private Function BuildTopoGraph(ByVal buildGeom As IGeometry, ByVal topoGraph As ITopologyGraph, ByVal keepSelection As Boolean) As Boolean
If buildGeom Is Nothing OrElse topoGraph Is Nothing Then
Return False
End If
Select Case buildGeom.GeometryType
Case esriGeometryType.esriGeometryPolygon
Dim topoGraph4 As ITopologyGraph4 = TryCast(topoGraph, ITopologyGraph4)
topoGraph4.BuildFromPolygon(CType(buildGeom, IPolygon), keepSelection)
Return True
Case esriGeometryType.esriGeometryEnvelope
topoGraph.Build(CType(buildGeom, IEnvelope), keepSelection)
Return True
Case Else
Return False
End Select
End Function