xls xlsx csv 导出datatable

  public static DataSet ReadFile(string path, string name)
        {
            if (string.IsNullOrWhiteSpace(path) || string.IsNullOrWhiteSpace(name) || !File.Exists(path + name))
                return null;
            // ?excel
            string connstring = string.Empty;
            string strSql = string.Empty;
            if (name.EndsWith(".xls") || name.EndsWith(".xlsx"))
            {
                connstring = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + path + name + ";Extended Properties='Excel 8.0;HDR=YES;IMEX=1';";
                strSql = "select * from [sheet1$]";
            }
            // ?csvゅン
            else if (name.EndsWith(".csv"))
            {
                connstring = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + path + ";Extended Properties='text;HDR=YES;FMT=Delimited';";
                strSql = "select * from " + name;
            }
            else
            {
                return null;
            }
            DataSet ds = null;
            OleDbConnection conn = null;
            try
            {
                conn = new OleDbConnection(connstring);
                conn.Open();
                OleDbDataAdapter myCommand = null;

                myCommand = new OleDbDataAdapter(strSql, connstring);
                ds = new DataSet();
                myCommand.Fill(ds, "table1");
            }
            catch (Exception e)
            {
                throw e;
            }
            finally
            {
                conn.Close();
            }
            return ds;
        }