NPOI单元格样式

ICellStyle style4 = workbook.CreateCellStyle();
style4.BorderRight = NPOI.SS.UserModel.BorderStyle.Thin;
style4.BorderLeft = NPOI.SS.UserModel.BorderStyle.Thin;
style4.BorderTop = NPOI.SS.UserModel.BorderStyle.Thin;
style4.BorderBottom = NPOI.SS.UserModel.BorderStyle.Thin;
style4.Alignment=HorizontalAlignment.Center;//水平居中

//单元格背景色设置为灰色
style4.FillPattern = NPOI.SS.UserModel.FillPattern.SolidForeground;
 style4.FillForegroundColor = NPOI.HSSF.Util.HSSFColor.Grey50Percent.Index;

style.VerticalAlignment = VerticalAlignment.Top;//垂直居中 是用top

  style.WrapText = true;//允许换行