Socket.BeginDisconnect(Boolean, AsyncCallback, Object) Socket.BeginDisconnect(Boolean, AsyncCallback, Object) Socket.BeginDisconnect(Boolean, AsyncCallback, Object) Socket.BeginDisconnect(Boolean, AsyncCallback, Object) Method

Definition

Begins an asynchronous request to disconnect from a remote endpoint.

public:
 IAsyncResult ^ BeginDisconnect(bool reuseSocket, AsyncCallback ^ callback, System::Object ^ state);
public IAsyncResult BeginDisconnect (bool reuseSocket, AsyncCallback callback, object state);
member this.BeginDisconnect : bool * AsyncCallback * obj -> IAsyncResult
Public Function BeginDisconnect (reuseSocket As Boolean, callback As AsyncCallback, state As Object) As IAsyncResult
Parameters
reuseSocket
Boolean Boolean Boolean Boolean

true if this socket can be reused after the connection is closed; otherwise, false.

state
Object Object Object Object

An object that contains state information for this request.

Returns

An IAsyncResult object that references the asynchronous operation.

Exceptions

The operating system is Windows 2000 or earlier, and this method requires Windows XP.

An error occurred when attempting to access the socket.

Examples

The following code example creates a socket for asynchronous communication and sends some data to a remote host. When the data has been sent, Shutdown is called to stop the send and receive activity. Then BeginDisconnect is called to begin a disconnect request. When the request completes, the Connected property is queried to test whether the socket is disconnected.

      // Establish the remote endpoint for the socket.
      // For this example use local computer.
      IPHostEntry^ ipHostInfo = Dns::GetHostEntry( Dns::GetHostName() );
      IPAddress^ ipAddress = ipHostInfo->AddressList[ 0 ];
      IPEndPoint^ remoteEP = gcnew IPEndPoint( ipAddress,11000 );

      // Create a TCP/IP socket.
      Socket^ client = gcnew Socket( AddressFamily::InterNetwork,SocketType::Stream,ProtocolType::Tcp );

      // Connect to the remote endpoint.
      client->BeginConnect( remoteEP, gcnew AsyncCallback( ConnectCallback ), client );

      // Wait for connect.
      connectDone->WaitOne();

      // Send some data to the remote device.
      String^ data = "This is a string of data <EOF>";
      array<Byte>^buffer = Encoding::ASCII->GetBytes( data );
      client->BeginSend( buffer, 0, buffer->Length, static_cast<SocketFlags>(0), gcnew AsyncCallback( ClientSendCallback ), client );

      // Wait for send done.
      sendDone->WaitOne();

      // Release the socket.
      client->Shutdown( SocketShutdown::Both );
      client->BeginDisconnect( true, gcnew AsyncCallback( DisconnectCallback ), client );

      // Wait for the disconnect to complete.
      disconnectDone->WaitOne();
      if ( client->Connected )
            Console::WriteLine( "We're still connected" );
      else
            Console::WriteLine( "We're disconnected" );
   }

private:
   static void DisconnectCallback( IAsyncResult^ ar )
   {
      // Complete the disconnect request.
      Socket^ client = dynamic_cast<Socket^>(ar->AsyncState);
      client->EndDisconnect( ar );

      // Signal that the disconnect is complete.
      disconnectDone->Set();
   }

public:

    // Establish the remote endpoint for the socket.
    // For this example use local computer.
    IPHostEntry ipHostInfo = Dns.GetHostEntry(Dns.GetHostName());
    IPAddress ipAddress = ipHostInfo.AddressList[0];
    IPEndPoint remoteEP = new IPEndPoint(ipAddress, 11000);

    // Create a TCP/IP socket.
    Socket client = new Socket(AddressFamily.InterNetwork,
        SocketType.Stream, ProtocolType.Tcp);

    // Connect to the remote endpoint.
    client.BeginConnect(remoteEP, 
        new AsyncCallback(ConnectCallback), client);
        
    // Wait for connect.
    connectDone.WaitOne();

    // Send some data to the remote device.
    string data = "This is a string of data <EOF>";
    byte[] buffer = Encoding.ASCII.GetBytes(data);
    client.BeginSend(buffer, 0, buffer.Length, 0, new AsyncCallback(ClientSendCallback), client);
    // Wait for send done.
    sendDone.WaitOne();

    // Release the socket.
    client.Shutdown(SocketShutdown.Both);
    client.BeginDisconnect(true, new AsyncCallback(DisconnectCallback), client);

    // Wait for the disconnect to complete.
    disconnectDone.WaitOne();
    if (client.Connected)
        Console.WriteLine("We're still connected");
    else
        Console.WriteLine("We're disconnected");
}


private static void DisconnectCallback(IAsyncResult ar)
{ 
    // Complete the disconnect request.
    Socket client = (Socket) ar.AsyncState;
    client.EndDisconnect(ar);

    // Signal that the disconnect is complete.
    disconnectDone.Set();
}

Remarks

If you are using a connection-oriented protocol, you can call the BeginDisconnect method to request a disconnect from a remote endpoint. If reuseSocket is true, you can reuse the socket.

The BeginDisconnect method uses a separate thread to invoke the specified callback method. The EndDisconnect method blocks until the pending disconnect is complete. For additional information on writing callback methods, see Marshaling a Delegate as a Callback Method.

Note

If you receive a SocketException exception, use the SocketException.ErrorCode property to obtain the specific error code. After you have obtained this code, refer to the Windows Sockets version 2 API error code documentation in the MSDN library for a detailed description of the error.

Note

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

Applies to