C# SerialPort实现串口通讯的代码详解

private void btnwrite_click(object sender, eventargs e)
{
    serialport serialport = new serialport();
    serialport.portname = "com1";//串口名称
    serialport.baudrate = 9600; //获取或设置波特率
    serialport.parity = parity.even;//获取或设置校验位
    serialport.databits = 8;//获取或设置数据位默认值8
    serialport.stopbits = stopbits.one;// 停止位
    serialport.open();
    serialport.write("a");
    serialport.close();
}

serialport serialport = new serialport();
private void btnread_click(object sender, eventargs e)
{


    byte[] a = system.text.encoding.ascii.getbytes(" ");
    serialport.portname = "com1";//串口名称
    serialport.baudrate = 9600; //获取或设置波特率
    serialport.parity = parity.none;//获取或设置校验位
    serialport.databits = 8;//获取或设置数据位默认值8
    serialport.stopbits = stopbits.one;// 停止位
    serialport.datareceived += serialport_datareceived;
    serialport.open();
}


private void serialport_datareceived(object sender, serialdatareceivedeventargs e)
{
    byte[] b = new byte[8];
    int a = serialport.read(b, 0, 8);
    this.invoke(() =>
    {
        string s = bytetohex(b);
        txtvalue.text += s+system.environment.newline;
    });
}


public string bytetohex(byte[] bytes)
{
    string str = string.empty;
    foreach (byte byte in bytes)
    {
        str += string.format("{0:x2}", byte) + " ";
    }
    return str.trim();
}

using system.io.ports;


namespace scom
{
    public partial class frmmain : form
    {
        serialport serialport;
        public frmmain()
        {
            initializecomponent();
            init();
        }


        private void loadports()
        {
            cboport.items.clear();
            string[] port = system.io.ports.serialport.getportnames();
            foreach (var item in port)
            {
                cboport.items.add(item);
            }
            cboport.selectedindex = 0;
        }


        private void init()
        {
            loadports();
            object[] baudrate = { 4800, 9600, 19200, 38400, 57600, 115200, 230400 };
            cbobaudrate.items.addrange(baudrate);
            cbobaudrate.selectedindex = 1;


            cbodatabits.items.add(7);
            cbodatabits.items.add(8);
            cbodatabits.selectedindex = 1;


            cbostopbits.items.add("one");
            cbostopbits.items.add("onepointfive");
            cbostopbits.items.add("two");
            cbostopbits.selectedindex = 0;


            //parity
            cboparity.items.add("none");
            cboparity.items.add("even");
            cboparity.items.add("mark");
            cboparity.items.add("odd");
            cboparity.items.add("space");
            cboparity.selectedindex = 0;


            cbohandshaking.items.add("none");
            cbohandshaking.items.add("xonxoff");
            cbohandshaking.items.add("requesttosend");
            cbohandshaking.items.add("requesttosendxonxoff");
            cbohandshaking.selectedindex = 0;
            btncloseport.enabled = false;
        }


        private void btnrefresh_click(object sender, eventargs e)
        {
            loadports();
        }


        private void btnopenport_click(object sender, eventargs e)
        {
            if (serialport == null)
            {
                serialport = new serialport();
            }
            serialport.portname = cboport.text;//串口名称
            serialport.baudrate = int.parse(cbobaudrate.text); //获取或设置波特率
            serialport.parity = (parity)enum.parse(typeof(parity), cboparity.text);//获取或设置校验位
            serialport.databits = int.parse(cbodatabits.text);//获取或设置数据位默认值8
            serialport.stopbits = (stopbits)enum.parse(typeof(stopbits), cbostopbits.text);// 停止位
            serialport.handshake = (handshake)enum.parse(typeof(handshake), cbohandshaking.text);// 握手协议
            serialport.datareceived += serialport_datareceived;
            serialport.open();
            stsmain_lblstatus.text = "端口已打开";
            btnopenport.enabled = false;
            btncloseport.enabled = true;
        }


        private void serialport_datareceived(object sender, serialdatareceivedeventargs e)
        {
            this.invoke(new action(() =>
            {
                byte[] b = new byte[8];
                int a = serialport.read(b, 0, 8);
                string s = "";
                if (rdohex.checked)
                {
                    s = bytetohex(b);
                }
                else
                {
                    s = system.text.encoding.default.getstring(b);
                }
                txtreceive.appendtext(system.environment.newline+ s);
            }));
        }


        private void btncloseport_click(object sender, eventargs e)
        {
            if (serialport != null && serialport.isopen)
            {
                serialport.datareceived -= serialport_datareceived;
                serialport.close();
                stsmain_lblstatus.text = "端口已关闭";
                btnopenport.enabled = true;
                btncloseport.enabled = false;
            }
        }


        private void btnsend_click(object sender, eventargs e)
        {
            if (serialport == null || !serialport.isopen)
            {
                return;
            }
            serialport.write(txtsend.text);
        }


        private string bytetohex(byte[] bytes)
        {
            string str = string.empty;
            foreach (byte byte in bytes)
            {
                str += string.format("{0:x2}", byte) + " ";
            }
            return str.trim();
        }
    }
}