private void aTimer_Elapsed(object sender, ElapsedEventArgs s)

        {

            if (isOpen)

            {

                try

                {

                    //SetPortProperty();

                    //ScreenBox.Text += sp.ReadExisting();



                    //string overWord="over";

                    //sp.NewLine = overWord;

                    //ScreenBox.Text += sp.ReadLine();

                    ChangeText CText = delegate()//声明和定义一个匿名代理

                    {

                       // ScreenBox.Text += sp.ReadExisting();



                        string dataRev; 

                        byte[] byteRead=new byte[serialPort1.BytesToRead;            

                        sp.Read(byteRead, 0, byteRead.Length);

                        dataRev = Encoding.Default.GetString(byteRead);

                        ScreenBox.Text += dataRev;