/// <summary> /// DataTable导出到Excel的MemoryStream /// </summary> /// <param name="dtSource">源DataTable</param> /// <param name="strHeaderText">表头文本</param> public static MemoryStream ExportDt(DataTable dtSource, string strHeaderText) { var workbook = new HSSFWorkbook(); var sheet = workbook.CreateSheet() as HSSFSheet; var cellStyle = workbook.CreateBasicCellStyle(); HSSFCellStyle dateStyle = workbook.CreateBasicCellStyle(); var format = workbook.CreateDataFormat() as HSSFDataFormat; // dateStyle.DataFormat = format.GetFormat("yyyy-mm-dd HH:mm:ss"); dateStyle.DataFormat = format.GetFormat("yyyy-mm-dd"); //取得列宽 int[] arrColWidth = new int[dtSource.Columns.Count]; foreach (DataColumn item in dtSource.Columns) { arrColWidth[item.Ordinal] = Encoding.GetEncoding(936).GetBytes(item.ColumnName).Length + 6; } for (int i = 0; i < dtSource.Rows.Count; i++) { for (int j = 0; j < dtSource.Columns.Count; j++) { int intTemp = Encoding.GetEncoding(936).GetBytes(dtSource.Rows[i][j].ToString()).Length; if (intTemp > arrColWidth[j]) { arrColWidth[j] = intTemp; } } } int rowIndex = 0; foreach (DataRow row in dtSource.Rows) { #region 新建表,填充表头,填充列头,样式 if (rowIndex == 65535 || rowIndex == 0) { if (rowIndex != 0) { sheet = workbook.CreateSheet() as HSSFSheet; } #region 表头及样式 if (!string.IsNullOrEmpty(strHeaderText) && strHeaderText != "下载开票模板_Evan") { var headerRow = sheet.CreateRow(0) as HSSFRow; headerRow.HeightInPoints = 25; headerRow.CreateCell(0).SetCellValue(strHeaderText); var headStyle = workbook.CreateCellStyle() as HSSFCellStyle; headStyle.Alignment = NPOI.SS.UserModel.HorizontalAlignment.Center; var font = workbook.CreateFont() as HSSFFont; font.FontHeightInPoints = 16; font.Boldweight = 700; headStyle.SetFont(font); headerRow.GetCell(0).CellStyle = headStyle; sheet.AddMergedRegion(new CellRangeAddress(0, 0, 0, dtSource.Columns.Count - 1)); //headerRow.Dispose(); if (dtSource.Columns[dtSource.Columns.Count - 1].ColumnName == "编号") { sheet.SetColumnHidden(dtSource.Columns.Count - 1, true); } // sheet.SetColumnHidden(); } #endregion #region 列头及样式 { var rownum = 0; if (strHeaderText == "下载开票模板_Evan") { rownum = 0; } else { rownum = string.IsNullOrEmpty(strHeaderText) ? 0 : 1; } var headerRow = sheet.CreateRow(rownum) as HSSFRow; headerRow.HeightInPoints = 20; var headStyle = workbook.CreateCellStyle() as HSSFCellStyle; headStyle.Alignment = NPOI.SS.UserModel.HorizontalAlignment.Center; var font = workbook.CreateFont() as HSSFFont; font.FontHeightInPoints = 11; font.Boldweight = 600; headStyle.SetFont(font); headStyle.BorderLeft = BorderStyle.Thin; headStyle.BorderRight = BorderStyle.Thin; headStyle.BorderTop = BorderStyle.Thin; headStyle.BorderBottom = BorderStyle.Thin; foreach (DataColumn column in dtSource.Columns) { if (strHeaderText == "下载开票模板_Evan") { //headStyle.IsLocked = true; headerRow.CreateCell(column.Ordinal).CellStyle = headStyle; sheet.SetColumnWidth(column.Ordinal, (arrColWidth[column.Ordinal] + 1) * 256); headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName); } else { headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName); headerRow.GetCell(column.Ordinal).CellStyle = headStyle; //设置列宽 //sheet.SetColumnWidth(column.Ordinal, (arrColWidth[column.Ordinal] + 1) * 256); } } //sheet.CreateFreezePane(0, 1, 0, 1); //sheet.CreateFreezePane(1, 0, 1, 0); //headerRow.Dispose(); } #endregion if (strHeaderText == "下载开票模板_Evan") { rowIndex = 1; } else { rowIndex = string.IsNullOrEmpty(strHeaderText) ? 1 : 2; } } #endregion #region 填充内容 var dataRow = sheet.CreateRow(rowIndex) as HSSFRow; foreach (DataColumn column in dtSource.Columns) { var newCell = dataRow.CreateCell(column.Ordinal) as HSSFCell; newCell.CellStyle = cellStyle; string drValue = row[column].ToString(); #region 写单元格的值 switch (column.DataType.ToString()) { case "System.String": //字符串类型 double result; if (IsNumeric(drValue, out result)) { double.TryParse(drValue, out result); newCell.SetCellValue(result); break; } else { newCell.SetCellValue(drValue); break; } case "System.DateTime": //日期类型 DateTime dateV; if (DateTime.TryParse(drValue, out dateV)) { newCell.SetCellValue(dateV); newCell.CellStyle = dateStyle; //格式化显示 } break; case "System.Boolean": //布尔型 bool boolV = false; bool.TryParse(drValue, out boolV); newCell.SetCellValue(boolV); break; case "System.Int16": //整型 case "System.Int32": case "System.Int64": case "System.Byte": int intV = 0; int.TryParse(drValue, out intV); newCell.SetCellValue(intV); break; case "System.Decimal": //浮点型 case "System.Double": double doubV = 0; double.TryParse(drValue, out doubV); newCell.SetCellValue(doubV); break; case "System.DBNull": //空值处理 newCell.SetCellValue(""); break; default: newCell.SetCellValue(drValue); break; } #endregion if (strHeaderText == "下载开票模板_Evan") { if (column.ColumnName == "Booking Branch" || column.ColumnName == "Customer ID" || column.ColumnName == "EBBS relationship ID" || column.ColumnName == "Customer ID/counterparty ID" || column.ColumnName == "EBBS Master ID" || column.ColumnName == "分行代码" || column.ColumnName == "客户编码") { newCell.SetCellValue(drValue); } } } #endregion rowIndex++; } using (var ms = new MemoryStream()) { workbook.Write(ms); ms.Flush(); ms.Position = 0; //sheet.Dispose(); //workbook.Dispose(); return(ms); } }