ASP.NET MVC 导入Excel表格中的数据至数据库

1.导入工具类（ImportExcel.cs）

	public class ImportExcel
    {
        public static DataTable GetExcelDataTable(string filePath)
        {
            IWorkbook Workbook;
            DataTable table = new DataTable();
            try
            {
                using (FileStream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read))
                {
                    //XSSFWorkbook 适用XLSX格式，HSSFWorkbook 适用XLS格式
                    string fileExt = Path.GetExtension(filePath).ToLower();
                    if (fileExt == ".xls")
                    {
                        Workbook = new HSSFWorkbook(fileStream);
                    }
                    else if (fileExt == ".xlsx")
                    {
                        Workbook = new XSSFWorkbook(fileStream);
                    }
                    else
                    {
                        Workbook = null;
                    }
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }

            //定位在第一个sheet
            ISheet sheet = Workbook.GetSheetAt(0);
            //第一行为标题行
            IRow headerRow = sheet.GetRow(0);
            int cellCount = headerRow.LastCellNum;
            int rowCount = sheet.LastRowNum;

            //循环添加标题列
            for (int i = headerRow.FirstCellNum; i < cellCount; i++)
            {
                DataColumn column = new DataColumn(headerRow.GetCell(i).StringCellValue);
                table.Columns.Add(column);
            }

            //数据
            for (int i = (sheet.FirstRowNum + 1); i <= rowCount; i++)
            {
                IRow row = sheet.GetRow(i);
                DataRow dataRow = table.NewRow();
                if (row != null)
                {
                    for (int j = row.FirstCellNum; j < cellCount; j++)
                    {
                        if (row.GetCell(j) != null)
                        {
                            dataRow[j] = GetCellValue(row.GetCell(j));
                        }
                    }
                }
                table.Rows.Add(dataRow);
            }
            return table;
        }

        private static string GetCellValue(ICell cell)
        {
            if (cell == null)
            {
                return string.Empty;
            }

            switch (cell.CellType)
            {
                case CellType.Blank:
                    return string.Empty;
                case CellType.Boolean:
                    return cell.BooleanCellValue.ToString();
                case CellType.Error:
                    return cell.ErrorCellValue.ToString();
                case CellType.Numeric:
                case CellType.Unknown:
                default:
                    return cell.ToString();
                case CellType.String:
                    return cell.StringCellValue;
                case CellType.Formula:
                    try
                    {
                        HSSFFormulaEvaluator e = new HSSFFormulaEvaluator(cell.Sheet.Workbook);
                        e.EvaluateInCell(cell);
                        return cell.ToString();
                    }
                    catch
                    {
                        return cell.NumericCellValue.ToString();
                    }
            }
        }

        /// <summary>
        /// 大数据插入
        /// </summary>
        /// <param name="connectionString">目标库连接</param>
        /// <param name="TableName">目标表</param>
        /// <param name="dtSelect">来源数据</param>
        public static void SqlBulkCopyByDatatable(string connectionString, string TableName, DataTable dtSelect)
        {
            using (SqlConnection conn = new SqlConnection(connectionString))
            {
                using (SqlBulkCopy sqlbulkcopy = new SqlBulkCopy(connectionString, SqlBulkCopyOptions.UseInternalTransaction))
                {
                    try
                    {
                        sqlbulkcopy.DestinationTableName = TableName;
                        sqlbulkcopy.BatchSize = 20000;
                        sqlbulkcopy.BulkCopyTimeout = 0;//不限时间
                        for (int i = 0; i < dtSelect.Columns.Count; i++)
                        {
                            sqlbulkcopy.ColumnMappings.Add(dtSelect.Columns[i].ColumnName, dtSelect.Columns[i].ColumnName);
                        }
                        sqlbulkcopy.WriteToServer(dtSelect);
                    }
                    catch (System.Exception ex)
                    {
                        throw ex;
                    }
                }
            }
        }

        public static void RemoveEmpty(DataTable dt)
        {
            List<DataRow> removelist = new List<DataRow>();
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                bool IsNull = true;
                for (int j = 0; j < dt.Columns.Count; j++)
                {
                    if (!string.IsNullOrEmpty(dt.Rows[i][j].ToString().Trim()))
                    {
                        IsNull = false;
                    }
                }
                if (IsNull)
                {
                    removelist.Add(dt.Rows[i]);
                }
            }
            for (int i = 0; i < removelist.Count; i++)
            {
                dt.Rows.Remove(removelist[i]);
            }
        }
    }

2.编写导入代码（这里以学籍对象为例）

说明：有关学籍对象的信息可查看本人之前的文章：https://blog.csdn.net/weixin_45721343/article/details/103909626

		/// <summary>
        /// 导入
        /// </summary>
        /// <param name="file"></param>
        /// <returns></returns>
        [HttpPost]
        public int Import(HttpPostedFileBase file)
        {
            var fileName = file.FileName;
            var filePath = Server.MapPath(string.Format("~/{0}", "Files"));
            string path = Path.Combine(filePath, fileName);
            file.SaveAs(path);
            //从NPOI读取到的Excel的数据
            DataTable excelTable = new DataTable();
            excelTable = ImportExcel.GetExcelDataTable(path);
            ImportExcel.RemoveEmpty(excelTable);
            int result = 0;
            foreach (DataRow dataRow in excelTable.Rows)
            {
                XJ xj = new XJ();
                xj.xh = dataRow["xh"].ToString();
                bool flag = xjService.FindByXh(xj.xh);
                //判断该学号的学籍信息是否存在，若不存在则添加
                if (!flag)
                {
                    xj.xm = dataRow["xm"].ToString();
                    xj.xbm = Convert.ToInt32(dataRow["xbm"]);
                    xj.nj = dataRow["nj"].ToString();
                    xj.rxrq = Convert.ToDateTime(dataRow["rxrq"]);
                    xj.yxsh = dataRow["yxsh"].ToString();
                    xj.dsbh = dataRow["dsbh"].ToString();
                    xj.zydm = dataRow["zydm"].ToString();
                    xj.xslb = dataRow["xslb"].ToString();
                    result+=xjService.Add(xj);
                }
            }
            return result;
        }