Follow code is select line or arc ,use   selectByID method.

Sub Main3()

  Dim swApp As SldWorks.SldWorks

  Dim swModel As SldWorks.ModelDoc2, SwSelMgr As SelectionMgr

  Dim swMeasure As SldWorks.Measure

  Dim SwSkSeg As SketchSegment

    Set swApp = Application.SldWorks

    Set swModel = swApp.ActiveDoc

    ''

    With swModel

       Set SwSelMgr = .SelectionManager

       .Extension.SelectByID2 "Line1@Sketch1", "EXTSKETCHSEGMENT", 0, 0, 0, False, 0, Nothing, 0

       Set SwSkSeg = SwSelMgr.GetSelectedObject2(1)

       Debug.Print Round(SwSkSeg.GetLength, 6)

       .Extension.SelectByID2 "Arc1@Sketch1", "EXTSKETCHSEGMENT", 0, 0, 0, False, 0, Nothing, 0

       Set SwSkSeg = SwSelMgr.GetSelectedObject2(1)

       Debug.Print Round(SwSkSeg.GetLength, 6)

    End With

End Sub

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Help me.

traverse method ,select line or arc in SketchSegment

Thanks