//建立一個串列埠通訊SerialPort CurrentPort = null;CurrentPort = new SerialPort();                CurrentPort.ReadBufferSize = 128;                CurrentPort.PortName = comName;  //埠號                 CurrentPort.BaudRate = bandRate; //位元率                 CurrentPort.Parity =parity;//奇偶校驗                 CurrentPort.StopBits = stop;//停止位                 CurrentPort.DataBits = databit;//資料位                CurrentPort.ReadTimeout = 1000; //讀超時，即在1000內未讀到資料就引起超時異常                 //繫結資料接收事件，因為傳送是被動的，所以你無法主動去獲取別人傳送的程式碼，只能透過這個事件來處理                CurrentPort.DataReceived += Sp_DataReceived;                CurrentPort.Open();                                                           定義一個變數 byte[] receiveStr;                                   //繫結的事件處理函式         private static void Sp_DataReceived(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)        {            SerialPort sp = sender as SerialPort;            if (sp == null)                return;            byte[] readBuffer = new byte[sp.ReadBufferSize];            sp.Read(readBuffer, 0, readBuffer.Length);                        //賦值            receiveStr=readBuffer;//當然你可以透過轉換將byte[]轉換為字串。        }                        //你要求的按鈕事件可以這麼寫         private void button1_Click(object sender, EventArgs e)         {                 if(receiveStr!=null)                 {                     變數  xxx=receiveStr;                 }         }

使用C#中的串列埠類，然後進行串列埠類的初始化後【串列埠的設定，波特率，停止位等】，就可以進行串列埠的接收和傳送資料了。