npoi 如何设置单元格为文本类型

ICellStyle style = workbook.CreateCellStyle();
            var font = workbook.CreateFont();
            font.FontHeightInPoints = 10;
            //font.FontName = "Arial";
            font.FontName = "仿宋";
            style.Alignment = NPOI.SS.UserModel.HorizontalAlignment.Center;
            style.VerticalAlignment = NPOI.SS.UserModel.VerticalAlignment.Center;
            style.SetFont(font);
            style.DataFormat = HSSFDataFormat.GetBuiltinFormat("TEXT");        //这个就是设置单元格为文本类型

var cell = sheet.GetRow(rowIndex).GetCell(colIndex);
 cell.CellStyle = style;
sheet.SetColumnWidth(colIndex, 20 * 256); // 设置列宽度为 20