This .NET class wraps the AcDbHatch::HatchEdgeType ObjectARX enum. 

The HatchEdgeType enumeration lists the geometry types used in hatch boundary edges.

Public Enum HatchEdgeType
  CircularArc = 2
  EllipticalArc = 3
  Line = 1
  Spline = 4
End Enum

public enum HatchEdgeType {
  CircularArc = 2,
  EllipticalArc = 3,
  Line = 1,
  Spline = 4
}