Excel连接字符串解析

        /// <summary>
        /// 导入Excel成DataTable
        /// </summary>
        /// <param name="filePath">文件路径 </param>
        /// <param name="version">Exl的版本(2003,2007)</param>
        /// <returns> </returns>
        public DataTable ExcelImportToDataTable(string filePath, string version)
        {
            DataTable dt = null;
            OleDbConnection Excelconn = null;
            LogHelper.WriteLog("初始化");
            if (version == "2003")
            {
                Excelconn =
                  new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source='" + filePath + @"';Extended Properties='Excel 8.0;HDR=NO;IMEX=1'" + @";");
            }
            else if (version == "2007")
            {
                LogHelper.WriteLog("判断为OleDbConnection");
                Excelconn =
                  new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source='" + filePath + @"';Extended Properties='Excel 12.0;HDR=NO;IMEX=1'" + @";");

           //当 IMEX=0 时为“汇出模式”，这个模式开启的 Excel 档案只能用来做“写入”用途。
           //当 IMEX=1 时为“汇入模式”，这个模式开启的 Excel 档案只能用来做“读取”用途。
           //当 IMEX=2 时为“连結模式”，这个模式开启的 Excel 档案可同时支援“读取”与“写入”用途。
                LogHelper.WriteLog("判断为OleDbConnection实例化成功");
            }
            else
            {
                throw new Exception("当前文件正在编辑,请关闭重试！");
            }

            //OleDbCommand cmd = null;
            //OleDbDataReader rdr = null;
            LogHelper.WriteLog("连接字符串初始化成功字符串的值:" + Excelconn.ConnectionString);

            try
            {
                Excelconn.Open();
                //cmd = Excelconn.CreateCommand();
                LogHelper.WriteLog("打开成功");
                dt = Excelconn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
                //string sheetName = "[" + dt.Rows[0]["TABLE_NAME"] + "]";  // TABLE_NAME 按照字母顺序排列 Rows[0]["TABLE_NAME"] 并不总是第一个sheet
                string sheetName = "";
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    if (dt.Rows[i]["TABLE_NAME"].ToString() == "Sheet1$")
                    {
                        sheetName = "[Sheet1$]";
                        isDefaultSheetNameExist = true;
                        break;
                    }
                }

                if (!isDefaultSheetNameExist) throw new Exception("默认的Sheet1不存在，请勿修改默认的Sheet名！");
                //cmd.CommandText = "SELECT * FROM " + sheetName + "";
                //rdr = cmd.ExecuteReader();
                string strSql = "SELECT * FROM " + sheetName + "";

                LogHelper.WriteLog("sql语句:" + strSql + "\n");
                OleDbDataAdapter da = new OleDbDataAdapter(strSql, Excelconn);
                LogHelper.WriteLog("初始化适配器");
                dt = new DataTable();
                LogHelper.WriteLog("初始化表格");
                da.Fill(dt);
                LogHelper.WriteLog("成功返回dt!");
                return dt;
            }
            catch (Exception etc)
            {
                LogHelper.WriteLog("ADO.NET连接EXCEL获取其中的数据异常:", etc);
                LogHelper.WriteLog(etc.Message + "\n");
                if (!(etc.InnerException == null))
                    LogHelper.WriteLog("内部异常", etc.InnerException);
                throw etc;
            }
            finally
            {
                //rdr.Close();
                Excelconn.Close();
                LogHelper.WriteLog("关闭ADO.NET数据连接,释放连接资源");
            }
        }

    /// <summary>
        /// 根据 MIME type 来判断文件的类型
        /// </summary>
        /// <returns></returns>
        private static string getExcelType()
        {
            if (_filemimeType == "application/vnd.ms-excel")
            {
                return "2003";
            }
            else if (_filemimeType == "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" ||
                     _filemimeType == "application/x-zip-compressed")   // IE6 下Excel2007 为 application/x-zip-compressed
            {
                return "2007";
            }
            else
            {
                return "";
            }
        }