private void Operate(string pFileName)
        {
            Excel.Application app = new Excel.Application();//打开一个Excel应用
            if (app == null)
            {
                return;
            }

            Workbooks wbs = app.Workbooks;
            _Workbook wb = wbs.Add(pFileName);//打开一个现有的工作薄
            Sheets shs = wb.Sheets;
            _Worksheet sh = (_Worksheet)shs.get_Item(1);//选择第一个Sheet页
            if (sh == null)
            {
                return;
            }

            Range r = sh.get_Range("B1", Missing.Value);
            if (System.Convert.ToString(r.Value2).Trim().Equals("my"))
            {
                //Do Something.
            }
        }

        private void ReleaseCOM(object pObj)
        {
            try
            {
                System.Runtime.InteropServices.Marshal.ReleaseComObject(pObj);
            }
            catch
            {
                throw new Exception("释放资源时发生错误！");
            }
            finally
            {
                pObj = null;
            }
        }

        private void Operate(string pFileName)
        { 
……
//释放资源
            ReleaseCOM(sh);
            ReleaseCOM(shs);
            ReleaseCOM(wb);
            ReleaseCOM(wbs);
            app.Quit();
            ReleaseCOM(app);
        }

        string  count = sh.UsedRange.Rows.Count.ToString();
        Range r = sh.get_Range("B100",Missing.Value);
        r.Formula = "=SUM(IF(FREQUENCY(MATCH(B1:B" + count + ",B1:B" + count + ",0),MATCH(B1:B" + count + ",B1:B" + count + ",0))>0,1))";
        Console.WriteLine(System.Convert.ToString(r.Value2));

        private DataTable LoadExcel(string pPath)
        {
            string connString = "Driver={Driver do Microsoft Excel(*.xls)};DriverId=790;SafeTransactions=0;ReadOnly=1;MaxScanRows=16;Threads=3;MaxBufferSize=2048;UserCommitSync=Yes;FIL=excel 8.0;PageTimeout=5;";
            connString += "DBQ=" + pPath;
            OdbcConnection conn = new OdbcConnection(connString);
            OdbcCommand cmd = new OdbcCommand();
            cmd.Connection = conn;
            //获取Excel中第一个Sheet名称，作为查询时的表名
            string sheetName = this.GetExcelSheetName(pPath);
            string sql = "select * from [" + sheetName.Replace('.', '#') + "$]";
            cmd.CommandText = sql;
            OdbcDataAdapter da = new OdbcDataAdapter(cmd);
            DataSet ds = new DataSet();
            try
            {                
                da.Fill(ds);
                return ds.Tables[0];
            }
            catch (Exception x)
            {
                ds = null;
                throw new Exception("从Excel文件中获取数据时发生错误！");
            }
            finally
            {
                cmd.Dispose();
                cmd = null;
                da.Dispose();
                da = null;
                if (conn.State == ConnectionState.Open)
                {
                    conn.Close();
                }
                conn = null;
            }
        }

        private string GetExcelSheetName(string pPath)
        {
            //打开一个Excel应用
            Excel.Application app = new Excel.Application();
            if (app == null)
            {
                throw new Exception("打开Excel应用时发生错误！");
            }
            Excel.Workbooks wbs = app.Workbooks;
            //打开一个现有的工作薄
            Excel._Workbook wb = wbs.Add(pPath);
            Excel.Sheets shs = wb.Sheets;
            //选择第一个Sheet页
            Excel._Worksheet sh = (Excel._Worksheet)shs.get_Item(1);
            string sheetName = sh.Name;

            ReleaseCOM(sh);
            ReleaseCOM(shs);
            ReleaseCOM(wb);
            ReleaseCOM(wbs);
            app.Quit();
            ReleaseCOM(app);
            return sheetName;
        }