range.Borders(Excel.XlBordersIndex.xlEdgeLeft).LineStyle = Excel.XlLineStyle.xlLineStyleNone
range.Borders(Excel.XlBordersIndex.xlEdgeRight).LineStyle = Excel.XlLineStyle.xlLineStyleNone
range.Borders(Excel.XlBordersIndex.xlEdgeTop).LineStyle = Excel.XlLineStyle.xlLineStyleNone
range.Borders(Excel.XlBordersIndex.xlEdgeBottom).LineStyle = Excel.XlLineStyle.xlLineStyleNone
range.Borders(Excel.XlBordersIndex.xlInsideHorizontal).LineStyle = Excel.XlLineStyle.xlLineStyleNone
range.Borders(Excel.XlBordersIndex.xlInsideVertical).LineStyle = Excel.XlLineStyle.xlLineStyleNone
Deletes borders around cells and between cells (through xlInsideHorizontaland xlInsideVertical). If you expect diagonal borders, turn on xlDiagonalDownand xlDiagonalUp.
Well, the code above was very verbose. The following should do it too:
For Each border in range.Borders
border.LineStyle = Excel.XlLineStyle.xlLineStyleNone
Next
See: http://msdn.microsoft.com/en-us/library/microsoft.office.interop.excel.borders.aspx
EDIT:
MSDN , :
range.Borders.LineStyle = Excel.XlLineStyle.xlLineStyleNone