EndDisconnect Method

Socket::EndDisconnect Method (IAsyncResult^)


Ends a pending asynchronous disconnect request.

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

void EndDisconnect(
	IAsyncResult^ asyncResult


Type: System::IAsyncResult^

An IAsyncResult object that stores state information and any user-defined data for this asynchronous operation.

Exception Condition

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


The Socket object has been closed.


asyncResult is null.


asyncResult was not returned by a call to the BeginDisconnect method.


EndDisconnect was previously called for the asynchronous connection.


An error occurred when attempting to access the socket. See the Remarks section for more information.


The disconnect request has timed out.

EndDisconnect completes a call to BeginDisconnect. The EndDisconnect method blocks until the disconnect completes. For information about asynchronous operations, see the Asynchronous Programming Overview topic in the MSDN library.


If you receive a SocketException, 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.


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

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. The callback delegate calls EndDisconnect to end the asynchronous 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.

      // 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.

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

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

   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.


.NET Framework
Available since 2.0
Return to top
© 2016 Microsoft