This example sets the font to bold in every other column in the visible range on the active worksheet.
For Each col In Spreadsheet1.ActiveSheet.VisibleRange.Columns
If col.Column Mod 2 = 0 Then col.Font.Bold = True
Next
The function in this example returns True if the entire current region for cell A1 is visible (if the current region extends outside the visible range, the function returns False).
Function IsCurrentRegionVisible()
Set cr = Spreadsheet1.ActiveSheet.Cells(1, 1).CurrentRegion
Set vr = Spreadsheet1.ActiveSheet.VisibleRange
Set ir = Spreadsheet1.Intersect(cr, vr)
IsCurrentRegionVisible = (ir.Address = cr.Address)
End Function