Imports System
Imports System.IO
Imports System.Net
Imports System.Net.Sockets
Imports System.Text
Imports Microsoft.VisualBasic
Class MyTcpListener
Public Shared Sub Main()
Dim server As TcpListener
server=nothing
Try
' Set the TcpListener on port 13000.
Dim port As Int32 = 13000
Dim localAddr As IPAddress = IPAddress.Parse("127.0.0.1")
server = New TcpListener(localAddr, port)
' Start listening for client requests.
server.Start()
' Buffer for reading data
Dim bytes(1024) As Byte
Dim data As String = Nothing
' Enter the listening loop.
While True
Console.Write("Waiting for a connection... ")
' Perform a blocking call to accept requests.
' You could also user server.AcceptSocket() here.
Dim client As TcpClient = server.AcceptTcpClient()
Console.WriteLine("Connected!")
data = Nothing
' Get a stream object for reading and writing
Dim stream As NetworkStream = client.GetStream()
Dim i As Int32
' Loop to receive all the data sent by the client.
i = stream.Read(bytes, 0, bytes.Length)
While (i <> 0)
' Translate data bytes to a ASCII string.
data = System.Text.Encoding.ASCII.GetString(bytes, 0, i)
Console.WriteLine("Received: {0}", data)
' Process the data sent by the client.
data = data.ToUpper()
Dim msg As Byte() = System.Text.Encoding.ASCII.GetBytes(data)
' Send back a response.
stream.Write(msg, 0, msg.Length)
Console.WriteLine("Sent: {0}", data)
i = stream.Read(bytes, 0, bytes.Length)
End While
' Shutdown and end connection
client.Close()
End While
Catch e As SocketException
Console.WriteLine("SocketException: {0}", e)
Finally
server.Stop()
End Try
Console.WriteLine(ControlChars.Cr + "Hit enter to continue....")
Console.Read()
End Sub 'Main
End Class 'MyTcpListener
