ListBox.GridLInesVertical Property
Syntax
GridLInesVertical as Integer
Draws vertical rules between columns in one of five styles. You can use the class constants for Borders to set the gridline styles.
They are:
BorderDefault (0): Default
BorderNone (1): None
BorderThinDotted (2): Thin Dotted
BorderThinSolid (3): Thin Solid
BorderThickSolid (4): Thick Solid
BorderDoubleThinSolid (5): Double Thin Solid
For example:
lb1.GridLinesVertical=ListBox.BorderThickSolid