Gets the segment index of the segment containing the nearest point. The segment index is relative to the part index. For example, if PartIndex = 2 and SegmentIndex = 0, it means segment 0 in part 2. Only relevant if calling GeometryEngine.NearestPoint, otherwise segment index is null.

public Nullable<int> SegmentIndex {get;}

Public ReadOnly Property SegmentIndex As Nullable(Of Integer)