local lnColumn, lcVariable
for lnColumn = 24 to 11 step -1
  lcVariable = "mx" + transform(lnColumn,'@L 99')
  if evaluate(lcVariable) > 0
    ThisForm.Grid1.DeleteColumn(lnColumn)
  endif
next

>thanks tore helpful reply,
>just i have other problem.
>lcVariable = "mx" + transform(lnColumn)
>
>i have 1 to 24 Columan, but 01 to 09( with 0)
>so "mx" + transform(lnColumn) result mx9 it should be mx09,
>thanks