UdpClient.JoinMulticastGroup Methode

Definition

Fügt einer Multicastgruppe einen UdpClient hinzu.

Überlädt

JoinMulticastGroup(IPAddress)

Fügt einer Multicastgruppe einen UdpClient hinzu.

JoinMulticastGroup(Int32, IPAddress)

Fügt einer Multicastgruppe einen UdpClient hinzu.

JoinMulticastGroup(IPAddress, Int32)

Fügt einer Multicasgruppe einen UdpClient mit angegebener Gültigkeitsdauer (TTL – Time To Live) hinzu.

JoinMulticastGroup(IPAddress, IPAddress)

Fügt einer Multicastgruppe einen UdpClient hinzu.

JoinMulticastGroup(IPAddress)

Fügt einer Multicastgruppe einen UdpClient hinzu.

public:
 void JoinMulticastGroup(System::Net::IPAddress ^ multicastAddr);
public void JoinMulticastGroup (System.Net.IPAddress multicastAddr);
member this.JoinMulticastGroup : System.Net.IPAddress -> unit
Public Sub JoinMulticastGroup (multicastAddr As IPAddress)

Parameter

multicastAddr
IPAddress

Die Multicast-IPAddress der Gruppe, der Sie beitreten möchten.

Ausnahmen

Der zugrunde liegende Socket wurde geschlossen.

Beim Zugreifen auf den Socket ist ein Fehler aufgetreten.

Die IP-Adresse ist nicht mit dem AddressFamily-Wert kompatibel, der das Adressierungsschema des Sockets definiert.

Beispiele

Im folgenden Codebeispiel wird veranschaulicht, wie Sie eine Multicastgruppe verknüpfen, indem Sie eine Multicastadresse angeben.

#using <System.dll>

using namespace System;
using namespace System::Net;
using namespace System::Net::Sockets;
using namespace System::Text;
using namespace System::IO;
using namespace System::Threading;

// The following Receive class is used by both the ClientOriginator and
// the ClientTarget class to receive data from one another..
public ref class Receive
{
public:

   // The following static method performs the actual data
   // exchange. In particular, it performs the following tasks:
   // 1)Establishes a communication endpoint.
   // 2)Receive data through this end point on behalf of the
   // caller.
   // 3) Returns the received data in ASCII format.
   static String^ ReceiveUntilStop( UdpClient^ c )
   {
      String^ strData = "";
      String^ Ret = "";
      ASCIIEncoding^ ASCII = gcnew ASCIIEncoding;
      
      // Establish the communication endpoint.
      IPEndPoint^ endpoint = gcnew IPEndPoint( IPAddress::IPv6Any,50 );
      while (  !strData->Equals( "Over" ) )
      {
         array<Byte>^data = c->Receive( endpoint );
         strData = ASCII->GetString( data );
         Ret = String::Concat( Ret, strData, "\n" );
      }

      return Ret;
   }

};


// The following Send class is used by both the ClientOriginator and
// ClientTarget classes to send data to one another.
public ref class Send
{
private:
   static array<Char>^greetings = {'H','e','l','l','o',' ','T','a','r','g','e','t','->'};
   static array<Char>^nice = {'H','a','v','e',' ','a',' ','n','i','c','e',' ','d','a','y','->'};
   static array<Char>^eom = {'O','v','e','r'};
   static array<Char>^tGreetings = {'H','e','l','l','o',' ','O','r','i','g','i','n','a','t','o','r','!'};
   static array<Char>^tNice = {'Y','o','u',' ','t','o','o','->'};

public:

   // The following static method sends data to the ClientTarget on
   // behalf of the ClientOriginator.
   static void OriginatorSendData( UdpClient^ c, IPEndPoint^ ep )
   {
      Console::WriteLine( gcnew String( greetings ) );
      c->Send( GetByteArray( greetings ), greetings->Length, ep );
      Thread::Sleep( 1000 );
      Console::WriteLine( gcnew String( nice ) );
      c->Send( GetByteArray( nice ), nice->Length, ep );
      Thread::Sleep( 1000 );
      Console::WriteLine( gcnew String( eom ) );
      c->Send( GetByteArray( eom ), eom->Length, ep );
   }


   // The following static method sends data to the ClientOriginator on
   // behalf of the ClientTarget.
   static void TargetSendData( UdpClient^ c, IPEndPoint^ ep )
   {
      Console::WriteLine( gcnew String( tGreetings ) );
      c->Send( GetByteArray( tGreetings ), tGreetings->Length, ep );
      Thread::Sleep( 1000 );
      Console::WriteLine( gcnew String( tNice ) );
      c->Send( GetByteArray( tNice ), tNice->Length, ep );
      Thread::Sleep( 1000 );
      Console::WriteLine( gcnew String( eom ) );
      c->Send( GetByteArray( eom ), eom->Length, ep );
   }


private:

   // Internal utility
   static array<Byte>^ GetByteArray( array<Char>^ChArray )
   {
      array<Byte>^Ret = gcnew array<Byte>(ChArray->Length);
      for ( int i = 0; i < ChArray->Length; i++ )
         Ret[ i ] = (Byte)ChArray[ i ];
      return Ret;
   }

};


// The ClientTarget class is the receiver of the ClientOriginator
// messages. The StartMulticastConversation method contains the
// logic for exchanging data between the ClientTarget and its
// counterpart ClientOriginator in a multicast operation.
public ref class ClientTarget
{
private:
   static UdpClient^ m_ClientTarget;
   static IPAddress^ m_GrpAddr;

public:

   // The following StartMulticastConversation method connects the UDP
   // ClientTarget with the ClientOriginator.
   // It performs the following main tasks:
   // 1)Creates a UDP client to receive data on a specific port and using
   // IPv6 addresses. The port is the same one used by the ClientOriginator
   // to define its communication endpoint.
   // 2)Joins or creates a multicast group at the specified address.
   // 3)Defines the endpoint port to send data to the ClientOriginator.
   // 4)Receives data from the ClientOriginator until the end of the
   // communication.
   // 5)Sends data to the ClientOriginator.
   // Note this method is the counterpart of the
   // ClientOriginator::ConnectOriginatorAndTarget().
   static void StartMulticastConversation()
   {
      String^ Ret;
      
      // Bind and listen on port 1000. Specify the IPv6 address family type.
      m_ClientTarget = gcnew UdpClient( 1000,AddressFamily::InterNetworkV6 );
      
      // Join or create a multicast group
      m_GrpAddr = IPAddress::Parse( "FF01::1" );
      
      // Use the overloaded JoinMulticastGroup method.
      // Refer to the ClientOriginator method to see how to use the other
      // methods.
      m_ClientTarget->JoinMulticastGroup( m_GrpAddr );
      
      // Define the endpoint data port. Note that this port number
      // must match the ClientOriginator UDP port number which is the
      // port on which the ClientOriginator is receiving data.
      IPEndPoint^ ClientOriginatordest = gcnew IPEndPoint( m_GrpAddr,2000 );
      
      // Receive data from the ClientOriginator.
      Ret = Receive::ReceiveUntilStop( m_ClientTarget );
      Console::WriteLine( "\nThe ClientTarget received: \n\n {0}\n", Ret );
      
      // Done receiving, now respond to the ClientOriginator.
      // Wait to make sure the ClientOriginator is ready to receive.
      Thread::Sleep( 2000 );
      Console::WriteLine( "\nThe ClientTarget sent:\n" );
      Send::TargetSendData( m_ClientTarget, ClientOriginatordest );
      
      // Exit the multicast conversation.
      m_ClientTarget->DropMulticastGroup( m_GrpAddr );
   }

};


// The following ClientOriginator class starts the multicast conversation
// with the ClientTarget class..
// It performs the following main tasks:
// 1)Creates a socket and binds it to the port on which to communicate.
// 2)Specifies that the connection must use an IPv6 address.
// 3)Joins or create a multicast group.
//   Note that the multicast address ranges to use are specified
//   in the RFC#2375.
// 4)Defines the endpoint to send the data to and starts the
// client target (ClientTarget) thread.
public ref class ClientOriginator
{
private:
   static UdpClient^ clientOriginator;
   static IPAddress^ m_GrpAddr;
   static IPEndPoint^ m_ClientTargetdest;
   static Thread^ m_t;

public:

   // The ConnectOriginatorAndTarget method connects the
   // ClientOriginator with the ClientTarget.
   // It performs the following main tasks:
   // 1)Creates a UDP client to receive data on a specific port
   //   using IPv6 addresses.
   // 2)Joins or create a multicast group at the specified address.
   // 3)Defines the endpoint port to send data to on the ClientTarget.
   // 4)Starts the ClientTarget thread that also creates the ClientTarget Object*.
   // Note this method is the counterpart of the
   // ClientTarget::StartMulticastConversation().
   static bool ConnectOriginatorAndTarget()
   {
      try
      {
         
         // Bind and listen on port 2000. This constructor creates a socket
         // and binds it to the port on which to receive data. The family
         // parameter specifies that this connection uses an IPv6 address.
         clientOriginator = gcnew UdpClient( 2000,AddressFamily::InterNetworkV6 );
         
         // Join or create a multicast group. The multicast address ranges
         // to use are specified in RFC#2375. You are free to use
         // different addresses.
         // Transform the String* address into the internal format.
         m_GrpAddr = IPAddress::Parse( "FF01::1" );
         
         // Display the multicast address used.
         Console::WriteLine( "Multicast Address: [ {0}]", m_GrpAddr );
         
         // Exercise the use of the IPv6MulticastOption.
         Console::WriteLine( "Instantiate IPv6MulticastOption(IPAddress)" );
         
         // Instantiate IPv6MulticastOption using one of the
         // overloaded constructors.
         IPv6MulticastOption^ ipv6MulticastOption = gcnew IPv6MulticastOption( m_GrpAddr );
         
         // Store the IPAdress multicast options.
         IPAddress^ group = ipv6MulticastOption->Group;
         __int64 interfaceIndex = ipv6MulticastOption->InterfaceIndex;
         
         // Display IPv6MulticastOption properties.
         Console::WriteLine( "IPv6MulticastOption::Group: [ {0}]", group );
         Console::WriteLine( "IPv6MulticastOption::InterfaceIndex: [ {0}]", interfaceIndex );
         
         // Instantiate IPv6MulticastOption using another
         // overloaded constructor.
         IPv6MulticastOption^ ipv6MulticastOption2 = gcnew IPv6MulticastOption( group,interfaceIndex );
         
         // Store the IPAdress multicast options.
         group = ipv6MulticastOption2->Group;
         interfaceIndex = ipv6MulticastOption2->InterfaceIndex;
         
         // Display the IPv6MulticastOption2 properties.
         Console::WriteLine( "IPv6MulticastOption::Group: [ {0} ]", group );
         Console::WriteLine( "IPv6MulticastOption::InterfaceIndex: [ {0} ]", interfaceIndex );
         
         // Join the specified multicast group using one of the
         // JoinMulticastGroup overloaded methods.
         clientOriginator->JoinMulticastGroup( (int)interfaceIndex, group );
         
         // Define the endpoint data port. Note that this port number
         // must match the ClientTarget UDP port number which is the
         // port on which the ClientTarget is receiving data.
         m_ClientTargetdest = gcnew IPEndPoint( m_GrpAddr,1000 );
         
         // Start the ClientTarget thread so it is ready to receive.
         m_t = gcnew Thread( gcnew ThreadStart( ClientTarget::StartMulticastConversation ) );
         m_t->Start();
         
         // Make sure that the thread has started.
         Thread::Sleep( 2000 );
         return true;
      }
      catch ( Exception^ e ) 
      {
         Console::WriteLine( "[ClientOriginator::ConnectClients] Exception: {0}", e );
         return false;
      }

   }


   // The SendAndReceive performs the data exchange
   // between the ClientOriginator and the ClientTarget classes.
   static String^ SendAndReceive()
   {
      String^ Ret = "";
      
      // Send data to ClientTarget.
      Console::WriteLine( "\nThe ClientOriginator sent:\n" );
      Send::OriginatorSendData( clientOriginator, m_ClientTargetdest );
      
      // Receive data from ClientTarget
      Ret = Receive::ReceiveUntilStop( clientOriginator );
      
      // Stop the ClientTarget thread
      m_t->Abort();
      
      // Abandon the multicast group.
      clientOriginator->DropMulticastGroup( m_GrpAddr );
      
      return Ret;
   }

};


//This is the console application entry point.
int main()
{
   
   // Join the multicast group.
   if ( ClientOriginator::ConnectOriginatorAndTarget() )
   {
      
      // Perform a multicast conversation with the ClientTarget.
      String^ Ret = ClientOriginator::SendAndReceive();
      Console::WriteLine( "\nThe ClientOriginator received: \n\n {0}", Ret );
   }
   else
   {
      Console::WriteLine( "Unable to Join the multicast group" );
   }
}

using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.IO;
using System.Threading;

namespace Mssc.TransportProtocols.Utilities
{

  // The following Receive class is used by both the ClientOriginator and
  // the ClientTarget class to receive data from one another..
  public class Receive
  {
    // The following static method performs the actual data
    // exchange. In particular, it performs the following tasks:
    // 1)Establishes a communication endpoint.
    // 2)Receive data through this end point on behalf of the
    // caller.
    // 3) Returns the received data in ASCII format.
    public static string ReceiveUntilStop(UdpClient c)
    {
        String strData = "";
        String Ret = "";
        ASCIIEncoding ASCII = new ASCIIEncoding();

        // Establish the communication endpoint.
        IPEndPoint endpoint = new IPEndPoint(IPAddress.IPv6Any, 50);

        while (!strData.Equals("Over"))
        {
          Byte[] data = c.Receive(ref endpoint);
          strData = ASCII.GetString(data);
          Ret += strData  + "\n";
        }
        return Ret;
    }
  }

  // The following Send class is used by both the ClientOriginator and
  // ClientTarget classes to send data to one another.
  public class Send
  {
    private static char[] greetings = { 'H', 'e', 'l', 'l', 'o', ' ',
                                      'T', 'a', 'r', 'g', 'e', 't', '.' };
    private static char[] nice      = { 'H', 'a', 'v', 'e', ' ', 'a', ' ', 'n', 'i',
                                      'c', 'e', ' ', 'd', 'a', 'y', '.' };
    private static char [] eom      = { 'O', 'v', 'e', 'r'};

    private static char[] tGreetings = { 'H', 'e', 'l', 'l', 'o', ' ',
                                       'O', 'r', 'i', 'g', 'i', 'n', 'a', 't', 'o', 'r', '!' };
    private static char[] tNice  = { 'Y', 'o', 'u', ' ', 't', 'o', 'o', '.'};

    // The following static method sends data to the ClientTarget on
    // behalf of the ClientOriginator.
    public static void OriginatorSendData(UdpClient c, IPEndPoint ep)
    {
      Console.WriteLine(new string(greetings));
      c.Send(GetByteArray(greetings), greetings.Length, ep);
      Thread.Sleep(1000);

      Console.WriteLine(new String(nice));
      c.Send(GetByteArray(nice), nice.Length, ep);

      Thread.Sleep(1000);
      Console.WriteLine(new String(eom));
      c.Send(GetByteArray(eom), eom.Length, ep);
    }

    // The following static method sends data to the ClientOriginator on
    // behalf of the ClientTarget.
    public static void TargetSendData(UdpClient c, IPEndPoint ep)
    {
      Console.WriteLine(new string(tGreetings));
      c.Send(GetByteArray(tGreetings), tGreetings.Length, ep);
      Thread.Sleep(1000);

      Console.WriteLine(new String(tNice));
      c.Send(GetByteArray(tNice), tNice.Length, ep);

      Thread.Sleep(1000);
      Console.WriteLine(new String(eom));
      c.Send(GetByteArray(eom), eom.Length, ep);
    }
    // Internal utility
    private static Byte[] GetByteArray(Char[] ChArray)
    {
      Byte[] Ret = new Byte[ChArray.Length];
      for (int i = 0; i < ChArray.Length; i++)
        Ret[i] = (Byte) ChArray[i];
      return Ret;
    }
  }

  // The ClientTarget class is the receiver of the ClientOriginator
  // messages. The StartMulticastConversation method contains the
  // logic for exchanging data between the ClientTarget and its
  // counterpart ClientOriginator in a multicast operation.
  public class ClientTarget
  {
    private static UdpClient m_ClientTarget;
    private static IPAddress m_GrpAddr;

    // The following StartMulticastConversation method connects the UDP
    // ClientTarget with the ClientOriginator.
    // It performs the following main tasks:
    // 1)Creates a UDP client to receive data on a specific port and using
    // IPv6 addresses. The port is the same one used by the ClientOriginator
    // to define its communication endpoint.
    // 2)Joins or creates a multicast group at the specified address.
    // 3)Defines the endpoint port to send data to the ClientOriginator.
    // 4)Receives data from the ClientOriginator until the end of the
    // communication.
    // 5)Sends data to the ClientOriginator.
    // Note this method is the counterpart of the
    // ClientOriginator.ConnectOriginatorAndTarget().
    public static void StartMulticastConversation()
    {
      string Ret;

      // Bind and listen on port 1000. Specify the IPv6 address family type.
      m_ClientTarget = new UdpClient(1000, AddressFamily.InterNetworkV6);

      // Join or create a multicast group
      m_GrpAddr = IPAddress.Parse("FF01::1");

      // Use the overloaded JoinMulticastGroup method.
      // Refer to the ClientOriginator method to see how to use the other
      // methods.
      m_ClientTarget.JoinMulticastGroup(m_GrpAddr);

      // Define the endpoint data port. Note that this port number
      // must match the ClientOriginator UDP port number which is the
      // port on which the ClientOriginator is receiving data.
      IPEndPoint ClientOriginatordest = new IPEndPoint(m_GrpAddr, 2000);

      // Receive data from the ClientOriginator.
      Ret = Receive.ReceiveUntilStop(m_ClientTarget);
      Console.WriteLine("\nThe ClientTarget received: " + "\n\n" + Ret + "\n");

      // Done receiving, now respond to the ClientOriginator.

      // Wait to make sure the ClientOriginator is ready to receive.
      Thread.Sleep(2000);

      Console.WriteLine("\nThe ClientTarget sent:\n");

      Send.TargetSendData(m_ClientTarget, ClientOriginatordest);

      // Exit the multicast conversation.
      m_ClientTarget.DropMulticastGroup(m_GrpAddr);
    }
  }

  // The following ClientOriginator class starts the multicast conversation
  // with the ClientTarget class..
  // It performs the following main tasks:
  // 1)Creates a socket and binds it to the port on which to communicate.
  // 2)Specifies that the connection must use an IPv6 address.
  // 3)Joins or create a multicast group.
  //   Note that the multicast address ranges to use are specified
  //   in the RFC#2375.
  // 4)Defines the endpoint to send the data to and starts the
  // client target (ClientTarget) thread.
  public class ClientOriginator
  {
    private static UdpClient clientOriginator;
    private static IPAddress m_GrpAddr;
    private static IPEndPoint m_ClientTargetdest;
    private static Thread m_t;

    // The ConnectOriginatorAndTarget method connects the
    // ClientOriginator with the ClientTarget.
    // It performs the following main tasks:
    // 1)Creates a UDP client to receive data on a specific port
    //   using IPv6 addresses.
    // 2)Joins or create a multicast group at the specified address.
    // 3)Defines the endpoint port to send data to on the ClientTarget.
    // 4)Starts the ClientTarget thread that also creates the ClientTarget object.
    // Note this method is the counterpart of the
    // ClientTarget.StartMulticastConversation().
    public static bool ConnectOriginatorAndTarget()
    {
      try
      {

        // Bind and listen on port 2000. This constructor creates a socket
        // and binds it to the port on which to receive data. The family
        // parameter specifies that this connection uses an IPv6 address.
        clientOriginator = new UdpClient(2000, AddressFamily.InterNetworkV6);

        // Join or create a multicast group. The multicast address ranges
        // to use are specified in RFC#2375. You are free to use
        // different addresses.

        // Transform the string address into the internal format.
        m_GrpAddr = IPAddress.Parse("FF01::1");

        // Display the multicast address used.
        Console.WriteLine("Multicast Address: [" + m_GrpAddr.ToString() + "]");

        // Exercise the use of the IPv6MulticastOption.
        Console.WriteLine("Instantiate IPv6MulticastOption(IPAddress)");

        // Instantiate IPv6MulticastOption using one of the
        // overloaded constructors.
        IPv6MulticastOption ipv6MulticastOption = new IPv6MulticastOption(m_GrpAddr);

        // Store the IPAdress multicast options.
        IPAddress group =  ipv6MulticastOption.Group;
        long interfaceIndex = ipv6MulticastOption.InterfaceIndex;

        // Display IPv6MulticastOption properties.
        Console.WriteLine("IPv6MulticastOption.Group: [" + group  + "]");
        Console.WriteLine("IPv6MulticastOption.InterfaceIndex: [" + interfaceIndex + "]");



        // Instantiate IPv6MulticastOption using another
        // overloaded constructor.
        IPv6MulticastOption ipv6MulticastOption2 = new IPv6MulticastOption(group, interfaceIndex);

        // Store the IPAdress multicast options.
        group =  ipv6MulticastOption2.Group;
        interfaceIndex = ipv6MulticastOption2.InterfaceIndex;

        // Display the IPv6MulticastOption2 properties.
        Console.WriteLine("IPv6MulticastOption.Group: [" + group  + "]");
        Console.WriteLine("IPv6MulticastOption.InterfaceIndex: [" + interfaceIndex + "]");

        // Join the specified multicast group using one of the
        // JoinMulticastGroup overloaded methods.
        clientOriginator.JoinMulticastGroup((int)interfaceIndex, group);


        // Define the endpoint data port. Note that this port number
        // must match the ClientTarget UDP port number which is the
        // port on which the ClientTarget is receiving data.
        m_ClientTargetdest = new IPEndPoint(m_GrpAddr, 1000);


        // Start the ClientTarget thread so it is ready to receive.
        m_t = new Thread(new ThreadStart(ClientTarget.StartMulticastConversation));
        m_t.Start();

        // Make sure that the thread has started.
        Thread.Sleep(2000);

        return true;
      }
      catch (Exception e)
      {
        Console.WriteLine("[ClientOriginator.ConnectClients] Exception: " + e.ToString());
        return false;
      }
    }

    // The SendAndReceive performs the data exchange
    // between the ClientOriginator and the ClientTarget classes.
    public static string SendAndReceive()
    {
      string Ret = "";


      // Send data to ClientTarget.
      Console.WriteLine("\nThe ClientOriginator sent:\n");
      Send.OriginatorSendData(clientOriginator, m_ClientTargetdest);

      // Receive data from ClientTarget
      Ret = Receive.ReceiveUntilStop(clientOriginator);

      // Stop the ClientTarget thread
      m_t.Abort();

      // Abandon the multicast group.
      clientOriginator.DropMulticastGroup(m_GrpAddr);


      return Ret;
    }

    //This is the console application entry point.
    public static void Main()
    {
      // Join the multicast group.
      if (ConnectOriginatorAndTarget())
      {
        // Perform a multicast conversation with the ClientTarget.
        string Ret = SendAndReceive();
        Console.WriteLine("\nThe ClientOriginator received: " + "\n\n" + Ret);
      }
      else
      {
        Console.WriteLine("Unable to Join the multicast group");
      }
    }
}
}
Imports System.Net
Imports System.Net.Sockets
Imports System.Text
Imports System.IO
Imports System.Threading

' The following Receive class is used by both the ClientOriginator and 
' the ClientTarget class to receive data from one another..

Public Class Receive
   
   ' The following static method performs the actual data
   ' exchange. In particular, it performs the following tasks:
   ' 1)Establishes a communication endpoint.
   ' 2)Receive data through this end point on behalf of the
   ' caller.
   ' 3) Returns the received data in ASCII format.
   Public Shared Function ReceiveUntilStop(c As UdpClient) As String
      Dim strData As [String] = ""
      Dim Ret As [String] = ""
      Dim ASCII As New ASCIIEncoding()
      
      ' Establish the communication endpoint.
      Dim endpoint As New IPEndPoint(IPAddress.IPv6Any, 50)
      
      While Not strData.Equals("Over")
         Dim data As [Byte]() = c.Receive(endpoint)
         strData = ASCII.GetString(data)
         Ret += strData + ControlChars.Lf
      End While
      Return Ret
   End Function 'ReceiveUntilStop
End Class

' The following Send class is used by both the ClientOriginator and 
' ClientTarget classes to send data to one another.

Public Class Send
   Private Shared greetings As Char() =  {"H"c, "e"c, "l"c, "l"c, "o"c, " "c, "T"c, "a"c, "r"c, "g"c, "e"c, "t"c, "."c}
   Private Shared nice As Char() =  {"H"c, "a"c, "v"c, "e"c, " "c, "a"c, " "c, "n"c, "i"c, "c"c, "e"c, " "c, "d"c, "a"c, "y"c, "."c}
   Private Shared eom As Char() =  {"O"c, "v"c, "e"c, "r"c}
   
   Private Shared tGreetings As Char() =  {"H"c, "e"c, "l"c, "l"c, "o"c, " "c, "O"c, "r"c, "i"c, "g"c, "i"c, "n"c, "a"c, "t"c, "o"c, "r"c, "!"c}
   Private Shared tNice As Char() =  {"Y"c, "o"c, "u"c, " "c, "t"c, "o"c, "o"c, "."c}
   
   
   ' The following static method sends data to the ClientTarget on 
   ' behalf of the ClientOriginator.
   Public Shared Sub OriginatorSendData(c As UdpClient, ep As IPEndPoint)
      Console.WriteLine(New String(greetings))
      c.Send(GetByteArray(greetings), greetings.Length, ep)
      Thread.Sleep(1000)
      
      Console.WriteLine(New [String](nice))
      c.Send(GetByteArray(nice), nice.Length, ep)
      
      Thread.Sleep(1000)
      Console.WriteLine(New [String](eom))
      c.Send(GetByteArray(eom), eom.Length, ep)
   End Sub
   
   
   ' The following static method sends data to the ClientOriginator on 
   ' behalf of the ClientTarget.
   Public Shared Sub TargetSendData(c As UdpClient, ep As IPEndPoint)
      Console.WriteLine(New String(tGreetings))
      c.Send(GetByteArray(tGreetings), tGreetings.Length, ep)
      Thread.Sleep(1000)
      
      Console.WriteLine(New [String](tNice))
      c.Send(GetByteArray(tNice), tNice.Length, ep)
      
      Thread.Sleep(1000)
      Console.WriteLine(New [String](eom))
      c.Send(GetByteArray(eom), eom.Length, ep)
   End Sub
   
   ' Internal utility 
   Public Shared Function GetByteArray(ChArray() As [Char]) As [Byte]()
      Dim Ret(ChArray.Length) As [Byte]
      
      Dim i As Integer
      For i = 0 To ChArray.Length - 1
         Ret(i) = AscW(ChArray(i))
      Next i 
      Return Ret
   End Function 'GetByteArray

End Class


' The ClientTarget class is the receiver of the ClientOriginator 
' messages. The StartMulticastConversation method contains the 
' logic for exchanging data between the ClientTarget and its 
' counterpart ClientOriginator in a multicast operation.

Public Class ClientTarget
   Private Shared m_ClientTarget As UdpClient
   Private Shared m_GrpAddr As IPAddress
   
   
   ' The following StartMulticastConversation method connects the UDP 
   ' ClientTarget with the ClientOriginator. 
   ' It performs the following main tasks:
   ' 1)Creates a UDP client to receive data on a specific port and using 
   ' IPv6 addresses. The port is the same one used by the ClientOriginator 
   ' to define its communication endpoint.
   ' 2)Joins or creates a multicast group at the specified address.  
   ' 3)Defines the endpoint port to send data to the ClientOriginator.
   ' 4)Receives data from the ClientOriginator until the end of the 
   ' communication.
   ' 5)Sends data to the ClientOriginator.
   ' Note this method is the counterpart of the 
   ' ClientOriginator.ConnectOriginatorAndTarget().
   Public Shared Sub StartMulticastConversation()
      Dim Ret As String
      
      ' Bind and listen on port 1000. Specify the IPv6 address family type.
      m_ClientTarget = New UdpClient(1000, AddressFamily.InterNetworkV6)
      
      ' Join or create a multicast group
      m_GrpAddr = IPAddress.Parse("FF01::1")
      
      ' Use the overloaded JoinMulticastGroup method.  
      ' Refer to the ClientOriginator method to see how to use the other 
      ' methods.
      m_ClientTarget.JoinMulticastGroup(m_GrpAddr)
      
      ' Define the endpoint data port. Note that this port number
      ' must match the ClientOriginator UDP port number which is the
      ' port on which the ClientOriginator is receiving data.
      Dim ClientOriginatordest As New IPEndPoint(m_GrpAddr, 2000)
      
      ' Receive data from the ClientOriginator.
      Ret = Receive.ReceiveUntilStop(m_ClientTarget)
      Console.WriteLine((ControlChars.Lf + "The ClientTarget received: " + ControlChars.Lf + ControlChars.Lf + Ret + ControlChars.Lf))
      
      ' Done receiving, now respond to the ClientOriginator.
      ' Wait to make sure the ClientOriginator is ready to receive.
      Thread.Sleep(2000)
      
      Console.WriteLine(ControlChars.Lf + "The ClientTarget sent:" + ControlChars.Lf)
      
      Send.TargetSendData(m_ClientTarget, ClientOriginatordest)
      
      ' Exit the multicast conversation. 
      m_ClientTarget.DropMulticastGroup(m_GrpAddr)
   End Sub
End Class


' The following ClientOriginator class starts the multicast conversation
' with the ClientTarget class.. 
' It performs the following main tasks:
' 1)Creates a socket and binds it to the port on which to communicate.
' 2)Specifies that the connection must use an IPv6 address.
' 3)Joins or create a multicast group. 
'   Note that the multicast address ranges to use are specified 
'   in the RFC#2375. 
' 4)Defines the endpoint to send the data to and starts the 
' client target (ClientTarget) thread.

Public Class ClientOriginator
   Private Shared clientOriginator As UdpClient
   Private Shared m_GrpAddr As IPAddress
   Private Shared m_ClientTargetdest As IPEndPoint
   Private Shared m_t As Thread
   
   
   ' The ConnectOriginatorAndTarget method connects the 
   ' ClientOriginator with the ClientTarget.
   ' It performs the following main tasks:
   ' 1)Creates a UDP client to receive data on a specific port 
   '   using IPv6 addresses. 
   ' 2)Joins or create a multicast group at the specified address.  
   ' 3)Defines the endpoint port to send data to on the ClientTarget.
   ' 4)Starts the ClientTarget thread that also creates the ClientTarget object.
   ' Note this method is the counterpart of the 
   ' ClientTarget.StartMulticastConversation().
   Public Shared Function ConnectOriginatorAndTarget() As Boolean
      Try
         ' Bind and listen on port 2000. This constructor creates a socket 
         ' and binds it to the port on which to receive data. The family 
         ' parameter specifies that this connection uses an IPv6 address.
         clientOriginator = New UdpClient(2000, AddressFamily.InterNetworkV6)
         
         ' Join or create a multicast group. The multicast address ranges 
         ' to use are specified in RFC#2375. You are free to use 
         ' different addresses.
         ' Transform the string address into the internal format.
         m_GrpAddr = IPAddress.Parse("FF01::1")
         
         ' Display the multicast address used.
         Console.WriteLine(("Multicast Address: [" + m_GrpAddr.ToString() + "]"))
         
         ' Exercise the use of the IPv6MulticastOption.
         Console.WriteLine("Instantiate IPv6MulticastOption(IPAddress)")
         
         ' Instantiate IPv6MulticastOption using one of the 
         ' overloaded constructors.
         Dim ipv6MulticastOption As New IPv6MulticastOption(m_GrpAddr)
         
         ' Store the IPAdress multicast options.
         Dim group As IPAddress = ipv6MulticastOption.Group
         Dim interfaceIndex As Long = ipv6MulticastOption.InterfaceIndex
         
         ' Display IPv6MulticastOption properties.
         Console.WriteLine(("IPv6MulticastOption.Group: [" + group.ToString() + "]"))
         Console.WriteLine(("IPv6MulticastOption.InterfaceIndex: [" + interfaceIndex.ToString() + "]"))
         
         ' Instantiate IPv6MulticastOption using another 
         ' overloaded constructor.
         Dim ipv6MulticastOption2 As New IPv6MulticastOption(group, interfaceIndex)
         
         ' Store the IPAdress multicast options.
         group = ipv6MulticastOption2.Group
         interfaceIndex = ipv6MulticastOption2.InterfaceIndex
         
         ' Display the IPv6MulticastOption2 properties.
         Console.WriteLine(("IPv6MulticastOption.Group: [" + group.ToString() + "]"))
         Console.WriteLine(("IPv6MulticastOption.InterfaceIndex: [" + interfaceIndex.ToString() + "]"))
         
         ' Join the specified multicast group using one of the 
         ' JoinMulticastGroup overloaded methods.
         clientOriginator.JoinMulticastGroup(Fix(interfaceIndex), group)
         
         ' Define the endpoint data port. Note that this port number
         ' must match the ClientTarget UDP port number which is the
         ' port on which the ClientTarget is receiving data.
         m_ClientTargetdest = New IPEndPoint(m_GrpAddr, 1000)
         
         ' Start the ClientTarget thread so it is ready to receive.
         m_t = New Thread(New ThreadStart(AddressOf ClientTarget.StartMulticastConversation))
         m_t.Start()
         
         ' Make sure that the thread has started.
         Thread.Sleep(2000)
         
         Return True
      Catch e As Exception
         Console.WriteLine(("[ClientOriginator.ConnectClients] Exception: " + e.ToString()))
         Return False
      End Try
   End Function 'ConnectOriginatorAndTarget
   
   
   ' The SendAndReceive performs the data exchange  
   ' between the ClientOriginator and the ClientTarget classes.
   Public Shared Function SendAndReceive() As String
      Dim Ret As String = ""
      
      ' Send data to ClientTarget.
      Console.WriteLine(ControlChars.Lf + "The ClientOriginator sent:" + ControlChars.Lf)
      Send.OriginatorSendData(clientOriginator, m_ClientTargetdest)
      
      ' Receive data from ClientTarget
      Ret = Receive.ReceiveUntilStop(clientOriginator)
      
      ' Stop the ClientTarget thread
      m_t.Abort()
      
      ' Abandon the multicast group.
      clientOriginator.DropMulticastGroup(m_GrpAddr)
      
      Return Ret
   End Function 'SendAndReceive
   
   
   'This is the console application entry point.
   Public Shared Sub Main()
      ' Join the multicast group.
      If ConnectOriginatorAndTarget() Then
         ' Perform a multicast conversation with the ClientTarget.
         Dim Ret As String = SendAndReceive()
         Console.WriteLine((ControlChars.Lf + "The ClientOriginator received: " + ControlChars.Lf + ControlChars.Lf + Ret))
      Else
         Console.WriteLine("Unable to Join the multicast group")
      End If
   End Sub
End Class

Hinweise

Die JoinMulticastGroup -Methode abonniert eine UdpClient Multicastgruppe mit dem angegebenen IPAddress. Nach dem Aufrufen der JoinMulticastGroup Methode sendet die zugrunde liegende Socket Gruppe ein IGMP-Paket (Internet Group Management Protocol) an den Router, der die Mitgliedschaft in der Multicastgruppe anfordert. Der Multicastadressbereich ist 224.0.0.0 bis 239.255.255.255. Wenn Sie eine Adresse außerhalb dieses Bereichs angeben oder wenn der Router, an den die Anforderung gesendet wird, nicht Multicast aktiviert ist, UdpClient wird ein SocketExceptionausgelöst. Wenn Sie einen SocketExceptionerhalten, verwenden Sie SocketException.ErrorCode , um den spezifischen Fehlercode abzurufen. Nachdem Sie diesen Code erhalten haben, finden Sie eine ausführliche Beschreibung des Fehlers in der Dokumentation zur Windows Sockets-API, Version 2 . Sobald der UdpClient mit dem Router als Mitglied der Multicastgruppe aufgeführt ist, kann er Multicast-Datagramme empfangen, die an die angegebene IPAddressgesendet werden.

Hinweis

Sie müssen die UdpClient mithilfe der Multicastportnummer erstellen. Andernfalls können Sie keine Multicast-Datagramme empfangen. Rufen Sie die Connect -Methode vor dem Aufrufen der JoinMulticastGroup -Methode nicht auf, sonst funktioniert die Receive Methode nicht. Sie müssen keiner Multicastgruppe angehören, um Datagramme an eine Multicast-IP-Adresse zu senden.

Bevor Sie einer Multicastgruppe beitreten, stellen Sie sicher, dass der Socket an den Port oder Endpunkt gebunden ist. Dazu rufen Sie einen der Konstruktoren auf, die einen Port oder einen Endpunkt als Parameter akzeptieren.

Um den Empfang von Multicast-Datagrammen zu beenden, rufen Sie die DropMulticastGroup -Methode auf, und geben Sie die IPAddress der Gruppe an, aus der Sie sich zurückziehen möchten.

Hinweis

Im IPv6-Fall gibt es mehrere Multicastadressbereiche, aus denen Sie auswählen können. Weitere Informationen finden Sie im IETF RFC 2375.

Hinweis

Sie können keinen UdpClient konstruierten ohne einen bestimmten lokalen Port aufrufen JoinMulticastGroup (d. a. mithilfe des UdpClient() Konstruktors oderUdpClient(AddressFamily)).

Siehe auch

Gilt für

JoinMulticastGroup(Int32, IPAddress)

Fügt einer Multicastgruppe einen UdpClient hinzu.

public:
 void JoinMulticastGroup(int ifindex, System::Net::IPAddress ^ multicastAddr);
public void JoinMulticastGroup (int ifindex, System.Net.IPAddress multicastAddr);
member this.JoinMulticastGroup : int * System.Net.IPAddress -> unit
Public Sub JoinMulticastGroup (ifindex As Integer, multicastAddr As IPAddress)

Parameter

ifindex
Int32

Der Schnittstellenindex, der der lokale IP-Adresse zugeordnet ist, an der die Multicastgruppe herzustellen ist.

multicastAddr
IPAddress

Die Multicast-IPAddress der Gruppe, der Sie beitreten möchten.

Ausnahmen

Der zugrunde liegende Socket wurde geschlossen.

Beim Zugreifen auf den Socket ist ein Fehler aufgetreten.

Beispiele

// Instantiate IPv6MulticastOption using another
// overloaded constructor.
IPv6MulticastOption^ ipv6MulticastOption2 = gcnew IPv6MulticastOption( group,interfaceIndex );

// Store the IPAdress multicast options.
group = ipv6MulticastOption2->Group;
interfaceIndex = ipv6MulticastOption2->InterfaceIndex;

// Display the IPv6MulticastOption2 properties.
Console::WriteLine( "IPv6MulticastOption::Group: [ {0} ]", group );
Console::WriteLine( "IPv6MulticastOption::InterfaceIndex: [ {0} ]", interfaceIndex );

// Join the specified multicast group using one of the
// JoinMulticastGroup overloaded methods.
clientOriginator->JoinMulticastGroup( (int)interfaceIndex, group );

// Instantiate IPv6MulticastOption using another
// overloaded constructor.
IPv6MulticastOption ipv6MulticastOption2 = new IPv6MulticastOption(group, interfaceIndex);

// Store the IPAdress multicast options.
group =  ipv6MulticastOption2.Group;
interfaceIndex = ipv6MulticastOption2.InterfaceIndex;

// Display the IPv6MulticastOption2 properties.
Console.WriteLine("IPv6MulticastOption.Group: [" + group  + "]");
Console.WriteLine("IPv6MulticastOption.InterfaceIndex: [" + interfaceIndex + "]");

// Join the specified multicast group using one of the
// JoinMulticastGroup overloaded methods.
clientOriginator.JoinMulticastGroup((int)interfaceIndex, group);
' Instantiate IPv6MulticastOption using another 
' overloaded constructor.
Dim ipv6MulticastOption2 As New IPv6MulticastOption(group, interfaceIndex)

' Store the IPAdress multicast options.
group = ipv6MulticastOption2.Group
interfaceIndex = ipv6MulticastOption2.InterfaceIndex

' Display the IPv6MulticastOption2 properties.
Console.WriteLine(("IPv6MulticastOption.Group: [" + group.ToString() + "]"))
Console.WriteLine(("IPv6MulticastOption.InterfaceIndex: [" + interfaceIndex.ToString() + "]"))

' Join the specified multicast group using one of the 
' JoinMulticastGroup overloaded methods.
clientOriginator.JoinMulticastGroup(Fix(interfaceIndex), group)

Hinweise

Stellen Sie vor dem Beitritt zu einer Multicastgruppe sicher, dass der Socket an den Port oder Endpunkt gebunden ist. Dazu rufen Sie einen der Konstruktoren auf, der einen Port oder einen Endpunkt als Parameter akzeptiert.

Der infindex Parameter wird verwendet, um eine Hardwareschnittstelle für denselben Link zu identifizieren.

Hinweis

Es stehen mehrere Multicastadressbereiche zur Auswahl. Siehe IETF RFC 2375.

Hinweis

Sie können keinen UdpClient konstruierten ohne einen bestimmten lokalen Port aufrufen JoinMulticastGroup (d. a. mithilfe des UdpClient.UdpClient() Konstruktors oderUdpClient.UdpClient(AddressFamily)).

Gilt für

JoinMulticastGroup(IPAddress, Int32)

Fügt einer Multicasgruppe einen UdpClient mit angegebener Gültigkeitsdauer (TTL – Time To Live) hinzu.

public:
 void JoinMulticastGroup(System::Net::IPAddress ^ multicastAddr, int timeToLive);
public void JoinMulticastGroup (System.Net.IPAddress multicastAddr, int timeToLive);
member this.JoinMulticastGroup : System.Net.IPAddress * int -> unit
Public Sub JoinMulticastGroup (multicastAddr As IPAddress, timeToLive As Integer)

Parameter

multicastAddr
IPAddress

Die IPAddress der Multicastgruppe, der Sie beitreten möchten.

timeToLive
Int32

Die TTL, gemessen in Routerhops.

Ausnahmen

Die bereitgestellte TTL liegt nicht zwischen 0 und 255

Der zugrunde liegende Socket wurde geschlossen.

Beim Zugreifen auf den Socket ist ein Fehler aufgetreten.

multicastAddr ist null.

Die IP-Adresse ist nicht mit dem AddressFamily-Wert kompatibel, der das Adressierungsschema des Sockets definiert.

Beispiele

Im folgenden Beispiel wird veranschaulicht, wie Sie eine Multicastgruppe verknüpfen, indem Sie zwei Parameter angeben: eine Multicastadresse und eine Zahl, die die TTL darstellt.

UdpClient^ udpClient = gcnew UdpClient;
// Creates an IPAddress to use to join and drop the multicast group.
IPAddress^ multicastIpAddress = IPAddress::Parse( "239.255.255.255" );

try
{
   // The packet dies after 50 router hops.
   udpClient->JoinMulticastGroup( multicastIpAddress, 50 );
}
catch ( Exception^ e ) 
{
   Console::WriteLine( e->ToString() );
}
UdpClient udpClient = new UdpClient();
// Creates an IPAddress to use to join and drop the multicast group.
IPAddress multicastIpAddress = IPAddress.Parse("239.255.255.255");

try{
     // The packet dies after 50 router hops.
     udpClient.JoinMulticastGroup(multicastIpAddress, 50);
}
catch ( Exception e ){
    Console.WriteLine( e.ToString());
}
Dim udpClient As New UdpClient()
' Creates an IP address to use to join and drop the multicast group.
Dim multicastIpAddress As IPAddress = IPAddress.Parse("239.255.255.255")

Try
   ' The packet dies after 50 router hops.
   udpClient.JoinMulticastGroup(multicastIpAddress, 50)
Catch e As Exception
   Console.WriteLine(e.ToString())
End Try

Hinweise

Die JoinMulticastGroup -Methode abonniert eine UdpClient Multicastgruppe mit dem angegebenen IPAddress. Nach dem Aufrufen der JoinMulticastGroup Methode sendet die zugrunde liegende Socket Gruppe ein IGMP-Paket (Internet Group Management Protocol) an den Router, der die Mitgliedschaft in der Multicastgruppe anfordert. Der Multicastadressbereich ist 224.0.0.0 bis 239.255.255.255. Wenn Sie eine Adresse außerhalb dieses Bereichs angeben oder wenn der Router, an den die Anforderung gesendet wird, nicht Multicast aktiviert ist, UdpClient wird ein SocketExceptionausgelöst. Wenn Sie einen SocketExceptionerhalten, verwenden Sie SocketException.ErrorCode , um den spezifischen Fehlercode abzurufen. Nachdem Sie diesen Code erhalten haben, finden Sie eine ausführliche Beschreibung des Fehlers in der Dokumentation zur Windows Sockets-API, Version 2 . Der timeToLive Parameter gibt an, wie viele Routerhops für ein Multicast-Datagramm zulässig sind, bevor sie verworfen werden. Sobald der UdpClient mit dem Router als Mitglied der Multicastgruppe aufgeführt ist, kann er Multicast-Datagramme empfangen, die an die angegebene IPAddressgesendet werden.

Hinweis

Sie müssen die UdpClient mithilfe der Multicastportnummer erstellen, andernfalls können Sie keine Multicast-Datagramme empfangen. Rufen Sie die Connect Methode nicht auf, bevor Sie die JoinMulticastGroup -Methode aufrufen, da die Empfangsmethode nicht funktioniert. Sie müssen keiner Multicastgruppe angehören, um Datagramme an eine Multicast-IP-Adresse zu senden.

Stellen Sie vor dem Beitreten einer Multicastgruppe sicher, dass der Socket an den Port oder Endpunkt gebunden ist. Dazu rufen Sie einen der Konstruktoren auf, die als Parameter einen Port oder einen Endpunkt akzeptieren.

Um den Empfang von Multicast-Datagrammen zu beenden, rufen Sie die DropMulticastGroup -Methode auf, und geben Sie die IPAddress der Gruppe an, aus der Sie sich zurückziehen möchten.

Hinweis

Sie können keinen UdpClient konstruierten ohne einen bestimmten lokalen Port aufrufen JoinMulticastGroup (d. a. mithilfe des UdpClient() Konstruktors oderUdpClient(AddressFamily)).

Siehe auch

Gilt für

JoinMulticastGroup(IPAddress, IPAddress)

Fügt einer Multicastgruppe einen UdpClient hinzu.

public:
 void JoinMulticastGroup(System::Net::IPAddress ^ multicastAddr, System::Net::IPAddress ^ localAddress);
public void JoinMulticastGroup (System.Net.IPAddress multicastAddr, System.Net.IPAddress localAddress);
member this.JoinMulticastGroup : System.Net.IPAddress * System.Net.IPAddress -> unit
Public Sub JoinMulticastGroup (multicastAddr As IPAddress, localAddress As IPAddress)

Parameter

multicastAddr
IPAddress

Die Multicast-IPAddress der Gruppe, der Sie beitreten möchten.

localAddress
IPAddress

Die lokale IPAddress.

Ausnahmen

Der zugrunde liegende Socket wurde geschlossen.

Beim Zugreifen auf den Socket ist ein Fehler aufgetreten.

Beispiele

Das folgende Codebeispiel zeigt die Verwendung der JoinMulticastGroup -Methode.

// Subscribe to a multicast group.
static void DoJoinMulticastGroup( UdpClient^ u, String^ mcast, String^ local )
{
   array<IPAddress^>^ multicastAddress = Dns::GetHostAddresses( mcast );

   u->JoinMulticastGroup( multicastAddress[0] );
   Console::WriteLine(  "Joined multicast Address {0}", multicastAddress );
}
// Subscribe to a multicast group.
public static void DoJoinMulticastGroup(UdpClient u, string mcast)
{
    IPAddress[] multicastAddress = Dns.GetHostAddresses(mcast);

    u.JoinMulticastGroup(multicastAddress[0]);
    Console.WriteLine("Joined multicast Address {0}",
        multicastAddress[0]);
}

Hinweise

Bevor Sie einer Multicastgruppe beitreten, stellen Sie sicher, dass der Socket an den Port oder Endpunkt gebunden ist. Dazu rufen Sie einen der Konstruktoren auf, der einen Port oder einen Endpunkt als Parameter akzeptiert.

Hinweis

Es stehen mehrere Multicastadressbereiche zur Auswahl. Sie finden sie im IETF RFC 2375.

Hinweis

Sie können keinen UdpClient konstruierten ohne einen bestimmten lokalen Port aufrufen JoinMulticastGroup (d. a. mithilfe des UdpClient() Konstruktors oderUdpClient(AddressFamily)).

Gilt für