C# 兩種方式實現Excel轉DataTable

兩種方式實現將Excel數據轉DataTable，現成的東西看得懂，拿來用就行了：

1、讀取Excel文件到DataSet中，再轉DataTable就不用我說了吧，基礎

        /// <summary>
        /// 讀取Excel文件到DataSet中
        /// </summary>
        /// <param name="filePath">文件路徑</param>
        /// <returns></returns>
        public static DataSet ToDataTable(string filePath)
        {
            string connStr = "";
            string fileType = System.IO.Path.GetExtension(filePath);
            if (string.IsNullOrEmpty(fileType)) return null;

            if (fileType == ".xls")
                connStr = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + filePath + ";" + ";Extended Properties=\"Excel 8.0;HDR=YES;IMEX=1\"";
            else
                connStr = "Provider=Microsoft.ACE.OLEDB.12.0;" + "Data Source=" + filePath + ";" + ";Extended Properties=\"Excel 12.0;HDR=YES;IMEX=1\"";
            string sql_F = "Select * FROM [{0}]";

            OleDbConnection conn = null;
            OleDbDataAdapter da = null;
            DataTable dtSheetName = null;

            DataSet ds = new DataSet();
            try
            {
                // 初始化連接，並打開
                conn = new OleDbConnection(connStr);
                conn.Open();

                // 獲取數據源的表定義元數據                        
                string SheetName = "";
                dtSheetName = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "TABLE" });

                // 初始化適配器
                da = new OleDbDataAdapter();
                for (int i = 0; i < dtSheetName.Rows.Count; i++)
                {
                    SheetName = (string)dtSheetName.Rows[i]["TABLE_NAME"];

                    if (SheetName.Contains("$") && !SheetName.Replace("'", "").EndsWith("$"))
                    {
                        continue;
                    }

                    da.SelectCommand = new OleDbCommand(String.Format(sql_F, SheetName), conn);
                    DataSet dsItem = new DataSet();
                    da.Fill(dsItem, SheetName);

                    ds.Tables.Add(dsItem.Tables[0].Copy());
                }
            }
            finally
            {
                // 關閉連接
                if (conn.State == ConnectionState.Open)
                {
                    conn.Close();
                    da.Dispose();
                    conn.Dispose();
                }
            }
            return ds;
        }

2、讀取Excel到DataTable中

/// <summary>  
        /// 將excel導入到datatable  
        /// </summary>  
        /// <param name="filePath">excel路徑</param>  
        /// <param name="isColumnName">第一行是否是列名</param>  
        /// <returns>返回datatable</returns>  
        public static DataTable ExcelToDataTable(string filePath, bool isColumnName)
        {
            DataTable dataTable = null;
            FileStream fs = null;
            DataColumn column = null;
            DataRow dataRow = null;
            IWorkbook workbook = null;
            ISheet sheet = null;
            IRow row = null;
            ICell cell = null;
            int startRow = 0;
            try
            {
                using (fs = System.IO.File.OpenRead(filePath))
                {
                    // 2007版本  
                    if (filePath.IndexOf(".xlsx") > 0)
                        workbook = new XSSFWorkbook(fs);
                    // 2003版本  
                    else if (filePath.IndexOf(".xls") > 0)
                        workbook = new HSSFWorkbook(fs);

                    if (workbook != null)
                    {
                        sheet = workbook.GetSheetAt(0);//讀取第一個sheet，當然也可以循環讀取每個sheet  
                        dataTable = new DataTable();
                        if (sheet != null)
                        {
                            int rowCount = sheet.LastRowNum;//總行數  
                            if (rowCount > 0)
                            {
                                IRow firstRow = sheet.GetRow(0);//第一行  
                                int cellCount = firstRow.LastCellNum;//列數  

                                //構建datatable的列  
                                if (isColumnName)
                                {
                                    startRow = 1;//如果第一行是列名，則從第二行開始讀取  
                                    for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
                                    {
                                        cell = firstRow.GetCell(i);
                                        if (cell != null)
                                        {
                                            if (cell.StringCellValue != null)
                                            {
                                                column = new DataColumn(cell.StringCellValue);
                                                dataTable.Columns.Add(column);
                                            }
                                        }
                                    }
                                }
                                else
                                {
                                    for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
                                    {
                                        column = new DataColumn("column" + (i + 1));
                                        dataTable.Columns.Add(column);
                                    }
                                }

                                //填充行  
                                for (int i = startRow; i <= rowCount; ++i)
                                {
                                    row = sheet.GetRow(i);
                                    if (row == null) continue;

                                    dataRow = dataTable.NewRow();
                                    for (int j = row.FirstCellNum; j < cellCount; ++j)
                                    {
                                        cell = row.GetCell(j);
                                        if (cell == null)
                                        {
                                            dataRow[j] = "";
                                        }
                                        else
                                        {
                                            //CellType(Unknown = -1,Numeric = 0,String = 1,Formula = 2,Blank = 3,Boolean = 4,Error = 5,)  
                                            switch (cell.CellType)
                                            {
                                                case CellType.Blank:
                                                    dataRow[j] = "";
                                                    break;
                                                case CellType.Numeric:
                                                    short format = cell.CellStyle.DataFormat;
                                                    //對時間格式（2015.12.5、2015/12/5、2015-12-5等）的處理  
                                                    if (format == 14 || format == 31 || format == 57 || format == 58)
                                                        dataRow[j] = cell.DateCellValue;
                                                    else
                                                        dataRow[j] = cell.NumericCellValue;
                                                    break;
                                                case CellType.String:
                                                    dataRow[j] = cell.StringCellValue;
                                                    break;
                                            }
                                        }
                                    }
                                    dataTable.Rows.Add(dataRow);
                                }
                            }
                        }
                    }
                }
                return dataTable;
            }
            catch (Exception ex)
            {
                if (fs != null)
                {
                    fs.Close();
                }
                throw ex;
            }
        }

不知道如何下載NPOI 動態庫的往下看：