TcpListener.Stop Method ()


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Closes the listener.

Namespace:   System.Net.Sockets
Assembly:  System (in System.dll)

Public Sub Stop

Exception Condition

Use the SocketException.ErrorCode property to obtain the specific error code. When you have obtained this code, you can refer to the Windows Sockets version 2 API error code documentation in MSDN for a detailed description of the error.

Stop closes the listener. Any unaccepted connection requests in the queue will be lost. Remote hosts waiting for a connection to be accepted will throw a SocketException. You are responsible for closing your accepted connections separately.


This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing in the .NET Framework.

Notes to Callers:

The Stop method also closes the underlying Socket, and creates a new Socket for the TcpListener. If you set any properties on the underlying Socket prior to calling the Stop method, those properties will not carry over to the new Socket.

The following code example demonstrates using the Stop method to close the underlying Socket.

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
            ' Set the TcpListener on port 13000.
         Dim port As Int32 = 13000
         Dim localAddr As IPAddress = IPAddress.Parse("")

         server = New TcpListener(localAddr, port)

         ' Start listening for client requests.

         ' 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()

            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
         End While
      Catch e As SocketException
         Console.WriteLine("SocketException: {0}", e)
      End Try

      Console.WriteLine(ControlChars.Cr + "Hit enter to continue....")
   End Sub 'Main

End Class 'MyTcpListener 

.NET Framework
Available since 1.1
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