串口实例，简单实用

【实例截图】

【核心代码】

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using hjCommunication;

namespace Test
{
    public partial class Form1 : Form
    {
        private hjSerialPortComm hjComm=new hjSerialPortComm();

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            UpdatePortNames();
            cmbPort.SelectedIndex = cmbPort.Items.Count > 0 ? 0 : -1;
            cmbBaudRate.SelectedIndex = cmbBaudRate.Items.Count > 0 ? 0 : -1;
            cmbDataBits.SelectedIndex = cmbDataBits.Items.Count - 1;
            cmbParity.SelectedIndex = cmbParity.Items.Count > 0 ? 0 : -1;
            cmbStopBits.SelectedIndex = cmbStopBits.Items.Count > 0 ? 0 : -1;
            cmbHandShake.SelectedIndex = cmbHandShake.Items.Count > 0 ? 0 : -1;

            UpdateControlStatus();
        }

        private void UpdatePortNames()
        {
            cmbPort.Items.Clear();
            cmbPort.Items.AddRange(hjSerialPortComm.GetPortNames());
        }
        private void UpdateControlStatus()
        {
            btnOpen.Enabled = cmbPort.SelectedIndex > -1;
            btnOpen.Text = hjComm.IsOpen ? "关闭" : "打开";
            btnRefleshPorts.Enabled = !hjComm.IsOpen;
            btnSend.Enabled = hjComm.IsOpen;
        }
        private void UpdateReceiveShow(string text)
        {
            txbReceive.AppendText(text);
            ShowMessage("已接收："   text);
        }
        private void ShowMessage(string msg)
        {
            txbMessage.AppendText(string.Format("\r\n{0} - {1}",DateTime.Now.ToString("HH:mm:ss"),msg));
        }

        private void cmbPort_SelectedIndexChanged(object sender, EventArgs e)
        {
            btnOpen.Enabled = cmbPort.SelectedIndex != -1;
        }

        private void btnOpen_Click(object sender, EventArgs e)
        {
            if (!hjComm.IsOpen)
            {
                hjComm.SetParams(cmbPort.Text, int.Parse(cmbBaudRate.SelectedItem.ToString()),
                    int.Parse(cmbDataBits.SelectedItem.ToString()), (System.IO.Ports.Parity)cmbParity.SelectedIndex
                    , (System.IO.Ports.StopBits)(cmbStopBits.SelectedIndex 1), (System.IO.Ports.Handshake)cmbHandShake.SelectedIndex);
                try
                {
                    hjComm.Open();
                    ShowMessage(String.Format("打开端口{0}成功!", hjComm.Comm.PortName));
                    hjComm.DataReceivedEvent  = hjComm_DataReceivedEvent;
                }
                catch (Exception ex)
                {
                    ShowMessage(String.Format("打开端口{0}失败：{1}", cmbPort.Text,ex.Message));
                }
            }
            else
            {
                hjComm.Close();
                ShowMessage(string.Format("关闭端口{0}成功!", hjComm.Comm.PortName));
                hjComm.DataReceivedEvent -= hjComm_DataReceivedEvent;
            }

            UpdateControlStatus();
        }

        private void hjComm_DataReceivedEvent(hjSerialPortComm arg1, string arg2)
        {
            if(this.InvokeRequired)
            {
                this.BeginInvoke(new Action<string>(UpdateReceiveShow), new object[] { arg2 });
            }
            else
                UpdateReceiveShow(arg2);
        }

        private void btnRefleshPorts_Click(object sender, EventArgs e)
        {
            UpdatePortNames();
            cmbPort.SelectedIndex = cmbPort.Items.Count > 0 ? 0 : -1;
            UpdateControlStatus();
            ShowMessage("已完成端口刷新!");
        }

        private void btnClearReceiveBuff_Click(object sender, EventArgs e)
        {
            if(txbReceive.TextLength==0)
                return;
            txbReceive.Clear();
            ShowMessage("已完成接收区清空!");
            UpdateControlStatus();
        }

        private void btnSend_Click(object sender, EventArgs e)
        {
            if (txbSend.TextLength > 0)
            {
                string textSend=txbSend.Text;
                hjComm.Send(textSend);
                txbSend.Clear();
                txbReceive.AppendText(textSend);
                ShowMessage("已发送："   textSend);
            }
        }

        private void rdbReceiveASCII_CheckedChanged(object sender, EventArgs e)
        {
            hjComm.ReceiveShowCodeType = rdbReceiveASCII.Checked ? CodeType.ASCII : CodeType.Hex;
        }

        private void rdbSendASCII_CheckedChanged(object sender, EventArgs e)
        {
            hjComm.SendCodeType = rdbSendASCII.Checked ? CodeType.ASCII : CodeType.Hex;
        }
        
    }
}