边框样式

//make the borders of cell F6 thick
worksheet.Cells[6, 6].Style.Border.Top.Style = ExcelBorderStyle.Thick;
worksheet.Cells[6, 6].Style.Border.Right.Style = ExcelBorderStyle.Thick;
worksheet.Cells[6, 6].Style.Border.Bottom.Style = ExcelBorderStyle.Thick;
worksheet.Cells[6, 6].Style.Border.Left.Style = ExcelBorderStyle.Thick;

//make the borders of cells A18 - J18 double and with a purple color
worksheet.Cells["A18:J18"].Style.Border.Top.Style = ExcelBorderStyle.Double;
worksheet.Cells["A18:J18"].Style.Border.Bottom.Style = ExcelBorderStyle.Double;
worksheet.Cells["A18:J18"].Style.Border.Top.Color.SetColor(Color.Purple);
worksheet.Cells["A18:J18"].Style.Border.Bottom.Color.SetColor(Color.Purple);