Imports System
Imports System.IO.Ports
Imports System.Threading

Public Class PortChat
    Shared _continue As Boolean
    Shared _serialPort As SerialPort

    Public Shared Sub Main()
        Dim name As String
        Dim message As String
        Dim sComparer As StringComparer = StringComparer.OrdinalIgnoreCase
        Dim readThread As Thread = New Thread(AddressOf Read)

        ' Create a new SerialPort object with default settings.
        _serialPort = New SerialPort()

        ' Allow the user to set the appropriate properties.
        _serialPort.PortName = SetPortName(_serialPort.PortName)
        _serialPort.BaudRate = SetPortBaudRate(_serialPort.BaudRate)
        _serialPort.Parity = SetPortParity(_serialPort.Parity)
        _serialPort.DataBits = SetPortDataBits(_serialPort.DataBits)
        _serialPort.StopBits = SetPortStopBits(_serialPort.StopBits)
        _serialPort.Handshake = SetPortHandshake(_serialPort.Handshake)

        ' Set the read/write timeouts
        _serialPort.ReadTimeout = 500
        _serialPort.WriteTimeout = 500

        _serialPort.Open()
        _continue = True
        readThread.Start()

        Console.Write("Name: ")
        name = Console.ReadLine()

        Console.WriteLine("Type QUIT to exit")

        While (_continue)
            message = Console.ReadLine()

            If sComparer.Equals("quit", message) Then
                _continue = False
            Else
                _serialPort.WriteLine( _
                    String.Format("<{0}>: {1}", name, message))
            End If
        end while

        readThread.Join()
        _serialPort.Close()
    End Sub

    Public Shared Sub Read()
        While (_continue)
            Try
                Dim message As String = _serialPort.ReadLine()
                Console.WriteLine(message)
            Catch ex As TimeoutException
                ' Do nothing
            End Try
        End While
    End Sub

    Public Shared Function SetPortName(ByVal defaultPortName As String) As String
        Dim newPortName As String

        Console.WriteLine("Available Ports:")
        Dim s As String
        For Each s In SerialPort.GetPortNames()
            Console.WriteLine("   {0}", s)
        Next s

        Console.Write("COM port({0}): ", defaultPortName)
        newPortName = Console.ReadLine()

        If newPortName = "" Then
            newPortName = defaultPortName
        End If
        Return newPortName
    End Function

    Public Shared Function SetPortBaudRate(ByVal defaultPortBaudRate As Integer) As Integer
        Dim newBaudRate As String

        Console.Write("Baud Rate({0}): ", defaultPortBaudRate)
        newBaudRate = Console.ReadLine()

        If newBaudRate = "" Then
            newBaudRate = defaultPortBaudRate.ToString()
        End If

        Return Integer.Parse(newBaudRate)
    End Function

    Public Shared Function SetPortParity(ByVal defaultPortParity As Parity) As Parity
        Dim newParity As String

        Console.WriteLine("Available Parity options:")
        Dim s As String
        For Each s In [Enum].GetNames(GetType(Parity))
            Console.WriteLine("   {0}", s)
        Next s

        Console.Write("Parity({0}):", defaultPortParity.ToString())
        newparity = Console.ReadLine()

        If newparity = "" Then
            newparity = defaultPortParity.ToString()
        End If

        Return CType([Enum].Parse(GetType(Parity), newParity), Parity)
    End Function

    Public Shared Function SetPortDataBits(ByVal defaultPortDataBits As Integer) As Integer
        Dim newDataBits As String

        Console.Write("Data Bits({0}): ", defaultPortDataBits)
        newDataBits = Console.ReadLine()

        If newDataBits = "" Then
            newDataBits = defaultPortDataBits.ToString()
        End If

        Return Integer.Parse(newDataBits)
    End Function

    Public Shared Function SetPortStopBits(ByVal defaultPortStopBits As StopBits) As StopBits
        Dim newStopBits As String

        Console.WriteLine("Available Stop Bits options:")
        Dim s As String
        For Each s In [Enum].GetNames(GetType(StopBits))
            Console.WriteLine("   {0}", s)
        Next s

        Console.Write("Stop Bits({0}):", defaultPortStopBits.ToString())
        newStopBits = Console.ReadLine()

        If newStopBits = "" Then
            newStopBits = defaultPortStopBits.ToString()
        End If

        Return CType([Enum].Parse(GetType(StopBits), newStopBits), StopBits)
    End Function

    Public Shared Function SetPortHandshake(ByVal defaultPortHandshake As Handshake) As Handshake
        Dim newHandshake As String

        Console.WriteLine("Available Handshake options:")
        Dim s As String
        For Each s In [Enum].GetNames(GetType(Handshake))
            Console.WriteLine("   {0}", s)
        Next s

        Console.Write("Stop Bits({0}):", defaultPortHandshake.ToString())
        newHandshake = Console.ReadLine()

        If newHandshake = "" Then
            newHandshake = defaultPortHandshake.ToString()
        End If

        Return CType([Enum].Parse(GetType(Handshake), newHandshake), Handshake)
    End Function
End Class

using System;
using System.IO.Ports;
using System.Threading;

public class PortChat
{
    static bool _continue;
    static SerialPort _serialPort;

    public static void Main()
    {
        string name;
        string message;
        StringComparer stringComparer = StringComparer.OrdinalIgnoreCase;
        Thread readThread = new Thread(Read);

        // Create a new SerialPort object with default settings.
        _serialPort = new SerialPort();

        // Allow the user to set the appropriate properties.
        _serialPort.PortName = SetPortName(_serialPort.PortName);
        _serialPort.BaudRate = SetPortBaudRate(_serialPort.BaudRate);
        _serialPort.Parity = SetPortParity(_serialPort.Parity);
        _serialPort.DataBits = SetPortDataBits(_serialPort.DataBits);
        _serialPort.StopBits = SetPortStopBits(_serialPort.StopBits);
        _serialPort.Handshake = SetPortHandshake(_serialPort.Handshake);

        // Set the read/write timeouts
        _serialPort.ReadTimeout = 500;
        _serialPort.WriteTimeout = 500;

        _serialPort.Open();
        _continue = true;
        readThread.Start();

        Console.Write("Name: ");
        name = Console.ReadLine();

        Console.WriteLine("Type QUIT to exit");

        while (_continue)
        {
            message = Console.ReadLine();

            if (stringComparer.Equals("quit", message))
            {
                _continue = false;
            }
            else
            {
                _serialPort.WriteLine(
                    String.Format("<{0}>: {1}", name, message) );
            }
        }

        readThread.Join();
        _serialPort.Close();
    }

    public static void Read()
    {
        while (_continue)
        {
            try
            {
                string message = _serialPort.ReadLine();
                Console.WriteLine(message);
            }
            catch (TimeoutException) { }
        }
    }

    public static string SetPortName(string defaultPortName)
    {
        string portName;

        Console.WriteLine("Available Ports:");
        foreach (string s in SerialPort.GetPortNames())
        {
            Console.WriteLine("   {0}", s);
        }

        Console.Write("COM port({0}): ", defaultPortName);
        portName = Console.ReadLine();

        if (portName == "")
        {
            portName = defaultPortName;
        }
        return portName;
    }

    public static int SetPortBaudRate(int defaultPortBaudRate)
    {
        string baudRate;

        Console.Write("Baud Rate({0}): ", defaultPortBaudRate);
        baudRate = Console.ReadLine();

        if (baudRate == "")
        {
            baudRate = defaultPortBaudRate.ToString();
        }

        return int.Parse(baudRate);
    }

    public static Parity SetPortParity(Parity defaultPortParity)
    {
        string parity;

        Console.WriteLine("Available Parity options:");
        foreach (string s in Enum.GetNames(typeof(Parity)))
        {
            Console.WriteLine("   {0}", s);
        }

        Console.Write("Parity({0}):", defaultPortParity.ToString());
        parity = Console.ReadLine();

        if (parity == "")
        {
            parity = defaultPortParity.ToString();
        }

        return (Parity)Enum.Parse(typeof(Parity), parity);
    }

    public static int SetPortDataBits(int defaultPortDataBits)
    {
        string dataBits;

        Console.Write("Data Bits({0}): ", defaultPortDataBits);
        dataBits = Console.ReadLine();

        if (dataBits == "")
        {
            dataBits = defaultPortDataBits.ToString();
        }

        return int.Parse(dataBits);
    }

    public static StopBits SetPortStopBits(StopBits defaultPortStopBits)
    {
        string stopBits;

        Console.WriteLine("Available Stop Bits options:");
        foreach (string s in Enum.GetNames(typeof(StopBits)))
        {
            Console.WriteLine("   {0}", s);
        }

        Console.Write("Stop Bits({0}):", defaultPortStopBits.ToString());
        stopBits = Console.ReadLine();

        if (stopBits == "")
        {
            stopBits = defaultPortStopBits.ToString();
        }

        return (StopBits)Enum.Parse(typeof(StopBits), stopBits);
    }

    public static Handshake SetPortHandshake(Handshake defaultPortHandshake)
    {
        string handshake;

        Console.WriteLine("Available Handshake options:");
        foreach (string s in Enum.GetNames(typeof(Handshake)))
        {
            Console.WriteLine("   {0}", s);
        }

        Console.Write("Stop Bits({0}):", defaultPortHandshake.ToString());
        handshake = Console.ReadLine();

        if (handshake == "")
        {
            handshake = defaultPortHandshake.ToString();
        }

        return (Handshake)Enum.Parse(typeof(Handshake), handshake);
    }
}