C# - Serial Port ASCII/HEX Format

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 System.IO.Ports;

namespace SerialTest1
{
    public partial class Form1 : Form
    {
        delegate void MyDelegate();      //델리게이트 선언(크로스 쓰레드 해결하기 위한 용도)

        bool SendForamt = true;          // true : ASCII   false : HEX
        bool ReceiveFormat = true;       // true : ASCII   false : HEX

        public Form1()
        {
            InitializeComponent();
            this.Disposed += new EventHandler(Form1_Disposed);
        }

        void Form1_Disposed(object sender, EventArgs e)
        {
            if (serialPort1.IsOpen)
            {
                serialPort1.DataReceived -= new SerialDataReceivedEventHandler(serialPort1_DataReceived);
                serialPort1.Close();
            }
        }

        void serialPort1_DataReceived(object sender, SerialDataReceivedEventArgs e)
        {
            byte[] array = new byte[1024];
            int temp;
            string str = string.Empty;
            temp = serialPort1.Read(array, 0, 1024);

            //아스키 값으로 받기
            if (ReceiveFormat)
            {
                MyDelegate dt = delegate()
                {
                    txt1.Text += "Receive Data : ";
                    for (int i = 0; i < temp; i++)
                    {
                        txt1.Text += (char)array[i];
                    }
                    txt1.Text += "\r\n";
                };
                this.Invoke(dt);
              
            }
            //HEX 값으로 받기
            else
            {
              
                for (int i = 0; i < temp; i++)
                {
                    str += string.Format("{0:x2} ", array[i]);
                }

                //헥사로 바꿔서 출력
                MyDelegate dt = delegate()
                {
                    txt1.Text += "Receive Data : ";
                    txt1.Text += str;
                    txt1.Text += "\r\n";
                };
                this.Invoke(dt);
            }
        }

        private void btnSend_Click(object sender, EventArgs e)
        {
            if (serialPort1.IsOpen)
            {
                //아스키 형태로 보내라
                if (SendForamt)
                {
                    serialPort1.Write(txt2.Text);
                }

                //HEX 형태로 보내라
                else
                {
                    string str = string.Empty;
                    byte[] arr = Encoding.ASCII.GetBytes(txt2.Text.ToCharArray());
                    foreach (byte b in arr)
                    {
                        str += string.Format("{0:x2} ", b);
                    }
                    serialPort1.Write(str);
                }
            }
            else
            {
                MessageBox.Show("포트가 연결되지 않았습니다.");
            }
        }

        private void cb1_SelectedIndexChanged(object sender, EventArgs e)
        {
            serialPort1.PortName = cbPortName.Text;
        }

        private void btnOpen_Click(object sender, EventArgs e)
        {
            try
            {
                serialPort1.Open();
                serialPort1.DataReceived += new SerialDataReceivedEventHandler(serialPort1_DataReceived);
                btnClose.Enabled = true;
                btnOpen.Enabled = false;
            }

            catch
            {
                MessageBox.Show("해당포트의 연결을 다시 확인하십시요");
            }
          
        }

        private void btnClose_Click(object sender, EventArgs e)
        {
            serialPort1.DataReceived -= new SerialDataReceivedEventHandler(serialPort1_DataReceived);
            serialPort1.Close();
            btnClose.Enabled = false;
            btnOpen.Enabled = true;
        }

        private void btnClear_Click(object sender, EventArgs e)
        {
            txt1.Text = "";
        }

        private void cbReceiveFormat_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (cbReceiveFormat.Text == "ASCII")
            {
                ReceiveFormat = true;
            }
            else
            {
                ReceiveFormat = false;
            }

        }

        private void cbSendFormat_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (cbSendFormat.Text == "ASCII")
            {
                SendForamt = true;
            }
            else
            {
                SendForamt = false;
            }
        }

        private void cbBaudrate_SelectedIndexChanged(object sender, EventArgs e)
        {
            serialPort1.BaudRate = int.Parse(cbBaudrate.Text);
        }

        private void cbDataBits_SelectedIndexChanged(object sender, EventArgs e)
        {
            serialPort1.DataBits = int.Parse(cbDataBits.Text);
        }

        private void cbStopBits_SelectedIndexChanged(object sender, EventArgs e)
        {
            switch(cbStopBits.SelectedIndex)
            {
                case 0:
                    serialPort1.StopBits = StopBits.One;
                    break;
                case 1:
                    serialPort1.StopBits = StopBits.Two;
                    break;
                default :
                    serialPort1.StopBits = StopBits.One;
                    break;
            }
          
        }

        private void cbParity_SelectedIndexChanged(object sender, EventArgs e)
        {
            switch (cbStopBits.SelectedIndex)
            {
                case 0:
                    serialPort1.Parity = Parity.None;
                    break;
                case 1:
                    serialPort1.Parity = Parity.Odd;
                    break;
                case 2:
                    serialPort1.Parity = Parity.Even;
                    break;
                default:
                    serialPort1.Parity = Parity.None;
                    break;
            }
        }
    }
}

출처: https://alsrns5052.tistory.com/entry/C-시리얼-통신 [Min's life]