The Hem feature relies on an edge to decide its direction. When editing the hem feature to flip its direction, Inventor identifies another edge and uses it for the hem feature. To do this programmatically, the HemDefinition.Edges collection is to be set. Currently the HemDefinition.Edges displays a "NotImplemented" error when trying to set it.
A workaround is to create a new Hem feature using the HemDefinition from the existing feature and use another edge in the process. The existing feature can be deleted after the new one is created. Also, it is important to set the end of part for retrieving the Edges collection from a Hem feature.
Here is a sample iLogic and C# code to flip the direction :
iLogic code snipet :
Dim oPartDoc As PartDocument
oPartDoc = ThisApplication.ActiveDocument
Dim oSheetMetalCompDef As SheetMetalComponentDefinition
oSheetMetalCompDef = oPartDoc.ComponentDefinition
Dim smFeatures As SheetMetalFeatures
smFeatures = oSheetMetalCompDef.Features
Dim oHems As HemFeatures
oHems = smFeatures.HemFeatures
Dim oHemFeature As HemFeature
oHemFeature = oHems.Item(1)
Dim oHemDef As HemDefinition
oHemDef = oHemFeature.Definition
oHemFeature.SetEndOfPart(True)
Dim currentHemEdge As Edge
Dim oHemEdgeColl As EdgeCollection
oHemEdgeColl = oHemDef.Edges
currentHemEdge = oHemDef.Edges.Item(1)
Dim oStartVertex As Vertex
oStartVertex = currentHemEdge.StartVertex
Dim oStopVertex As Vertex
oStopVertex = currentHemEdge.StopVertex
Dim edge1 As Edge
edge1 = oSheetMetalCompDef.SurfaceBodies(1).Edges(1)
Dim edge2 As Edge
edge2 = oSheetMetalCompDef.SurfaceBodies(1).Edges(3)
Dim oEdgeColl As EdgeCollection
= ThisApplication.TransientObjects.CreateEdgeCollection
If edge1.StartVertex Is oStartVertex
And edge1.StopVertex Is oStopVertex Then
oEdgeColl.Add(edge2)
ElseIf edge2.StartVertex Is oStartVertex
And edge2.StopVertex Is oStopVertex Then
oEdgeColl.Add(edge1)
Else MessageBox.Show("Sorry, could not flip direction. The hem Feature does Not use a known edge",
"iLogic HemFeature Flip direction")
oHemFeature.SetEndOfPart(False)
ReturnEndIf
Dim oHemDefNew As HemDefinition
oHemDefNew = oHemDef.Copy
oHemDefNew.Edges = oEdgeColl
Dim hemFeatureName AsString
hemFeatureName = oHemFeature.Name
oHemFeature.Delete
Dim oHemFeatureNew As HemFeature
oHemFeatureNew = oHems.Add(oHemDefNew)
oHemFeatureNew.Name = hemFeatureName
C# code snipet :
PartDocument oPartDoc
= (PartDocument)_invApp.ActiveDocument;
SheetMetalComponentDefinition oSheetMetalCompDef
= oPartDoc.ComponentDefinition
as SheetMetalComponentDefinition;
SheetMetalFeatures smFeatures
= oSheetMetalCompDef.Features as SheetMetalFeatures;
HemFeatures oHems = smFeatures.HemFeatures;
HemFeature oHemFeature = oHems[1];
HemDefinition oHemDef = oHemFeature.Definition;
// Important to get the right edge from the HemDefinitionoHemFeature.SetEndOfPart(true );
EdgeCollection oHemEdgeColl = oHemDef.Edges;
Edge currentHemEdge = oHemDef.Edges[1];
Vertex oStartVertex = currentHemEdge.StartVertex;
Vertex oStopVertex = currentHemEdge.StopVertex;
Edge edge1
= oSheetMetalCompDef.SurfaceBodies[1].Edges[1];
Edge edge2
= oSheetMetalCompDef.SurfaceBodies[1].Edges[3];
EdgeCollection oEdgeColl =
_invApp.TransientObjects.CreateEdgeCollection();
if (object.ReferenceEquals(edge1.StartVertex, oStartVertex) &&
object.ReferenceEquals(edge1.StopVertex, oStopVertex))
{// edge1 is the hem edge. //'s use another edge to flip the hem featureoEdgeColl.Add(edge2);
}elseif (object.ReferenceEquals(edge2.StartVertex, oStartVertex) &&
object.ReferenceEquals(edge2.StopVertex, oStopVertex))
{// edge2 is the hem edge. //'s use another edge to flip the hem featureoEdgeColl.Add(edge1);
}else{ MessageBox.Show(@"Sorry, could not flip direction. The hem feature does not use a known edge", "HemFeature Flip direction" );
oHemFeature.SetEndOfPart(false );
return ;
}HemDefinition oHemDefNew = oHemDef.Copy();
oHemDefNew.Edges = oEdgeColl;
string hemFeatureName = null;
hemFeatureName = oHemFeature.Name;
// Delete the existing hem featureoHemFeature.Delete();
HemFeature oHemFeatureNew = default (HemFeature);
oHemFeatureNew = oHems.Add(oHemDefNew);
oHemFeatureNew.Name = hemFeatureName;