C#读取Excel和CSV为DataTable

#region 获取Excel数据        /// <summary>        /// 根据Excel物理路径、表名(Sheet名)获取数据集        /// </summary>        /// <param name="FileFullPath">excel文件完整路径</param>        /// <param name="SheetName">工作簿名称</param>        /// <returns></returns>        public DataTable GetExcelToDataTableBySheet(string FileFullPath, string SheetName)        {            string strConn = "Provider=Microsoft.Ace.OleDb.12.0;" + "data source=" + FileFullPath + ";Extended Properties='Excel 12.0; HDR=YES; IMEX=1'"; //此连接可以操作.xls与.xlsx文件,【HDR为YES表示首行为字段,为NO表示首行为数据】            //string strConn = "Provider=Microsoft.Jet.OleDb.4.0;" + "data source=" + FileFullPath + ";Extended Properties='Excel 8.0; HDR=YES; IMEX=1'";//旧版连接            OleDbConnection conn = new OleDbConnection(strConn);            conn.Open();            DataSet ds = new DataSet();            OleDbDataAdapter odda = new OleDbDataAdapter(string.Format("SELECT * FROM [{0}]", SheetName), conn);//("select * from [Sheet1$]", conn);            odda.Fill(ds);            conn.Close();            return ds.Tables[0];        }        /// <summary>        /// 根据Excel物理路径获取Excel文件中所有表名        /// </summary>        /// <param name="FileFullPath">excel文件完整路径</param>        /// <returns></returns>        public String[] GetExcelSheetNames(string FileFullPath)        {            OleDbConnection objConn = null;            System.Data.DataTable dt = null;            try            {                string strConn = "Provider=Microsoft.Ace.OleDb.12.0;" + "data source=" + FileFullPath + ";Extended Properties='Excel 12.0; HDR=YES; IMEX=1'"; //此连接可以操作.xls与.xlsx文件                objConn = new OleDbConnection(strConn);                objConn.Open();                dt = objConn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);                if (dt == null)                {                    return null;                }                String[] excelSheets = new String[dt.Rows.Count];                int i = 0;                foreach (DataRow row in dt.Rows)                {                    excelSheets[i] = row["TABLE_NAME"].ToString();                    i++;                }                return excelSheets;            }            catch            {                return null;            }            finally            {                if (objConn != null)                {                    objConn.Close();                    objConn.Dispose();                }                if (dt != null)                {                    dt.Dispose();                }            }        }        #endregion/// <summary>    /// 获取CSV导入的数据    /// </summary>    /// <param name="filePath">文件所在路径(不包含文件名)</param>    /// <param name="fileName">文件名称</param>    /// <returns></returns>    public DataTable GetCsvData(string filePath, string fileName)    {        string path = Path.Combine(filePath, fileName);        string connString = @"Driver={Microsoft Text Driver (*.txt; *.csv)};Dbq=" + filePath + ";Extensions=asc,csv,tab,txt;";        try        {            using (OdbcConnection odbcConn = new OdbcConnection(connString))            {                odbcConn.Open();                OdbcCommand oleComm = new OdbcCommand();                oleComm.Connection = odbcConn;                oleComm.CommandText = "select * from [" + fileName + "]";                OdbcDataAdapter adapter = new OdbcDataAdapter(oleComm);                DataSet ds = new DataSet();                adapter.Fill(ds);                odbcConn.Close();                return ds.Tables[0];            }        }        catch (Exception ex)        {            throw ex;        }    }