本文实例为大家分享了C#使用Datatable导出Excel的具体代码，供大家参考，具体内容如下

using NPOI.SS.UserModel;using NPOI.XSSF.UserModel;using System;using System.Collections.Generic;using System.Data;using System.IO;using System.Linq;using Newtonsoft.Json;namespace EasyFrame.Common{ /// <summary> ///title调用信息 /// </summary> public class ChartTitle { /// <summary> /// 调用名 /// </summary> public string CallName { get; set; } /// <summary> /// 标头信息 /// </summary> public List<ChartName> SetNameList { get; set; } } public class ChartName { /// <summary> /// 一级标头 /// </summary> public string Name { get; set; } /// <summary> /// 二级标头 /// </summary> public List<string> ChartChildNameList { get; set; } } public class ExcelHelper { // /// <summary> /// Datatable导出Excel /// </summary> /// <param name="dt">数据</param> /// <param name="list">表头</param> /// <param name="counts">总条数</param> /// <param name="filePath">保存地址</param> /// <returns></returns> public static MemoryStream WriteExcel(DataTable dt, List<ChartTitle> objlist, string filePath) { var list = objlist.FirstOrDefault(a => a.CallName == "ccc").SetNameList; if (!string.IsNullOrEmpty(filePath) && null != dt && dt.Rows.Count > 0) { XSSFWorkbook book = new XSSFWorkbook(); NPOI.SS.UserModel.ISheet sheet = book.CreateSheet(dt.TableName); ICell cell = null; ICellStyle style = book.CreateCellStyle(); IFont font = book.CreateFont();//创建字体样式 IFont fonts = book.CreateFont();//创建字体样式 IFont fontss = book.CreateFont();//创建字体样式 font.Color = NPOI.HSSF.Util.HSSFColor.Red.Index;//设置字体颜色 ICellStyle styles = book.CreateCellStyle(); //红色 fonts.Color = NPOI.HSSF.Util.HSSFColor.Green.Index; ICellStyle styless = book.CreateCellStyle(); //绿色 fontss.Color = NPOI.HSSF.Util.HSSFColor.Blue.Index; ICellStyle stylesss = book.CreateCellStyle(); //蓝色 styless.SetFont(fonts); styles.SetFont(font); stylesss.SetFont(fontss); style.Alignment = HorizontalAlignment.Center; NPOI.SS.UserModel.IRow row1 = sheet.CreateRow(0); NPOI.SS.UserModel.IRow row2 = sheet.CreateRow(1); var row = row1; int num = 0;//记录列 var d = true;//是否第一次加载到二级表单 #region 创建表头 //两行单列 for (int i = 0; i < list.Count; i++) { if (!d) { row = row1; d = true; } if (list[i].ChartChildNameList == null) { cell = row.CreateCell(num); sheet.SetColumnWidth(num, 15 * 256); cell.SetCellValue(list[i].Name); cell.CellStyle = style; sheet.AddMergedRegion(new NPOI.SS.Util.CellRangeAddress(0, 1, num, num)); num++; continue; } //两行多列 var count = list[i].ChartChildNameList.Count; //列数 cell = row.CreateCell(num); cell.SetCellValue(list[i].Name); cell.CellStyle = style; sheet.AddMergedRegion(new NPOI.SS.Util.CellRangeAddress(0, 0, num, count + num - 1)); if (d) { d = false; row = row2; } var t = 0; var rang = sheet.GetRow(1); for (int j = 0; j < count; j++) { sheet.SetColumnWidth(num + t, 5 * 256); cell = row.CreateCell(num + t); cell.SetCellValue(list[i].ChartChildNameList[j]); cell.CellStyle = style; t++; } num = num + count; } #endregion 创建表头 #region 写入数据 int customs = 0;//记录列数 int clouns = 0;//记录行数 filePath = string.Format(filePath, "XXX"); #region 导出操作 var data1 = JsonConvert.DeserializeObject<List<类名>>(dt.Rows[0][0].ToString()); foreach (var item in data1) { NPOI.SS.UserModel.IRow rows = sheet.CreateRow(clouns + 2); customs = 0; rows.CreateCell(customs).SetCellValue(Convert.ToString(item.No)); customs++; rows.CreateCell(customs).SetCellValue(Convert.ToString(item.LotteryOpenNo)); customs++; for (int i = 0; i < item.Wan.Length; i++) { if (item.LotteryOpenNo.Split(',')[0] == item.Wan[i].ToString()) { cell = rows.CreateCell(customs); cell.SetCellValue(item.Wan[i]); cell.CellStyle = styles; customs++; } else { rows.CreateCell(customs).SetCellValue(item.Wan[i]); customs++; } } for (int j = 0; j < item.Qian.Length; j++) { if (item.LotteryOpenNo.Split(',')[1] == item.Qian[j].ToString()) { cell = rows.CreateCell(customs); cell.SetCellValue(item.Qian[j]); cell.CellStyle = styles; customs++; } else { rows.CreateCell(customs).SetCellValue(item.Qian[j]); customs++; } } for (int k = 0; k < item.Bai.Length; k++) { if (item.LotteryOpenNo.Split(',')[2] == item.Bai[k].ToString()) { cell = rows.CreateCell(customs); cell.SetCellValue(item.Bai[k]); cell.CellStyle = styles; customs++; } else { rows.CreateCell(customs).SetCellValue(item.Bai[k]); customs++; } } for (int l = 0; l < item.Shi.Length; l++) { if (item.LotteryOpenNo.Split(',')[3] == (item.Shi[l].ToString())) { cell = rows.CreateCell(customs); cell.SetCellValue(item.Shi[l]); cell.CellStyle = styles; customs++; } else { rows.CreateCell(customs).SetCellValue(item.Shi[l]); customs++; } } for (int m = 0; m < item.Ge.Length; m++) { if (item.LotteryOpenNo.Split(',')[4] == (item.Ge[m].ToString())) { cell = rows.CreateCell(customs); cell.SetCellValue(item.Ge[m]); cell.CellStyle = styles; customs++; } else { rows.CreateCell(customs).SetCellValue(item.Ge[m]); customs++; } } for (int n = 0; n < item.Fen.Length; n++) { if (item.LotteryOpenNo.Contains(item.Fen[n].ToString())) { cell = rows.CreateCell(customs); cell.SetCellValue(item.Fen[n]); cell.CellStyle = styles; customs++; } else { rows.CreateCell(customs).SetCellValue(item.Fen[n]); customs++; } } clouns++; } #endregion #endregion 写入数据 // 写入到客户端 using (System.IO.MemoryStream ms = new System.IO.MemoryStream()) { book.Write(ms); using (FileStream fs = new FileStream(filePath, FileMode.Create, FileAccess.Write)) { byte[] data = ms.ToArray(); fs.Write(data, 0, data.Length); fs.Flush(); } book = null; return ms; } } return null; } }}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。