This .NET class wraps the AcDb::GridLineType ObjectARX enum. These values describe the grid lines of a table.

Public Enum GridLineType
  AllGridLines = &H3f
  HorizontalBottom = 4
  HorizontalGridLines = 7
  HorizontalInside = 2
  HorizontalTop = 1
  InnerGridLines = &H12
  InvalidGridLine = 0
  OuterGridLines = &H2d
  VerticalGridLines = &H38
  VerticalInside = &H10
  VerticalLeft = 8
  VerticalRight = &H20
End Enum

public enum GridLineType {
  AllGridLines = 0x3f,
  HorizontalBottom = 4,
  HorizontalGridLines = 7,
  HorizontalInside = 2,
  HorizontalTop = 1,
  InnerGridLines = 0x12,
  InvalidGridLine = 0,
  OuterGridLines = 0x2d,
  VerticalGridLines = 0x38,
  VerticalInside = 0x10,
  VerticalLeft = 8,
  VerticalRight = 0x20
}