UdpClient.JoinMulticastGroup 方法

參考

定義

命名空間:: System.Net.Sockets

組件:: System.Net.Sockets.dll

組件:: System.dll

組件:: netstandard.dll

重要

部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。

將 UdpClient 新增至多播群組。

多載

JoinMulticastGroup(IPAddress)	將 UdpClient 新增至多播群組。
JoinMulticastGroup(Int32, IPAddress)	將 UdpClient 新增至多播群組。
JoinMulticastGroup(IPAddress, Int32)	將 UdpClient 新增至具有指定存留時間（TTL）的多播群組。
JoinMulticastGroup(IPAddress, IPAddress)	將 UdpClient 新增至多播群組。

JoinMulticastGroup(IPAddress)

來源:: UDPClient.cs

來源:: UDPClient.cs

來源:: UDPClient.cs

將 UdpClient 新增至多播群組。

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)

參數

multicastAddr: IPAddress

您想要加入之群組的多播 IPAddress。

例外狀況

ObjectDisposedException

基礎 Socket 已關閉。

SocketException

存取套接字時發生錯誤。

ArgumentException

IP 位址與定義套接字尋址配置的 AddressFamily 值不相容。

範例

下列程式代碼範例示範如何藉由提供多播位址來聯結多播群組。

#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

備註

JoinMulticastGroup 方法會使用指定的 IPAddress，將 UdpClient 訂閱至多播群組。呼叫 JoinMulticastGroup 方法之後，基礎 Socket 會將因特網群組管理通訊協定（IGMP）封包傳送至要求多播群組成員資格的路由器。多播位址範圍是 224.0.0.0 到 239.255.255.255。如果您指定超出此範圍的位址，或提出要求的路由器未啟用多播，UdpClient 會擲回 SocketException。如果您收到 SocketException，請使用 SocketException.ErrorCode 取得特定的錯誤碼。取得此程式代碼之後，您可以參閱 Windows Sockets 第 2 版 API 錯誤碼檔，以取得錯誤的詳細描述。一旦將路由器列為多播群組成員的 UdpClient，它就能夠接收傳送至指定之 IPAddress的多播數據報。

注意

您必須使用多播埠號碼建立 UdpClient;否則，您將無法接收多播的數據報。在呼叫 JoinMulticastGroup 方法之前，請勿呼叫 Connect 方法，否則 Receive 方法將無法運作。您不需要屬於多播群組，即可將數據報傳送至多播IP位址。

加入多播群組之前，請確定套接字已系結至埠或端點。您可以藉由呼叫接受埠或端點做為參數的其中一個建構函式來執行此動作。

若要停止接收多播數據報，請呼叫 DropMulticastGroup 方法，並提供您想要從中撤銷的群組 IPAddress。

注意

在 IPv6 案例中，您可以選擇數個多播地址範圍。請參閱 IETF RFC 2375。

注意

您無法在沒有特定本機埠的情況下，在建構 UdpClient 上呼叫 JoinMulticastGroup（也就是使用 UdpClient() 或 UdpClient(AddressFamily) 建構函式）。

另請參閱

DropMulticastGroup(IPAddress)

適用於

JoinMulticastGroup(Int32, IPAddress)

來源:: UDPClient.cs

來源:: UDPClient.cs

來源:: UDPClient.cs

將 UdpClient 新增至多播群組。

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)

參數

ifindex: Int32

與要加入多播群組之本機 IP 位址相關聯的介面索引。

multicastAddr: IPAddress

您想要加入之群組的多播 IPAddress。

例外狀況

ObjectDisposedException

基礎 Socket 已關閉。

SocketException

存取套接字時發生錯誤。

範例

// 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)

備註

加入多播群組之前，請確定套接字已系結至埠或端點。您可以呼叫其中一個接受埠或連接點做為參數的建構函式來執行此動作。

infindex 參數可用來識別相同連結上的硬體介面。

注意

有數個多播位址範圍可供選擇。請參閱 IETF RFC 2375。

注意

您無法在沒有特定本機埠的情況下，在建構 UdpClient 上呼叫 JoinMulticastGroup（也就是使用 UdpClient.UdpClient() 或 UdpClient.UdpClient(AddressFamily) 建構函式）。

適用於

JoinMulticastGroup(IPAddress, Int32)

來源:: UDPClient.cs

來源:: UDPClient.cs

來源:: UDPClient.cs

將 UdpClient 新增至具有指定存留時間（TTL）的多播群組。

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)

參數

multicastAddr: IPAddress

要加入的多播群組 IPAddress。

timeToLive: Int32

以路由器躍點測量的存留時間（TTL）。

例外狀況

ArgumentOutOfRangeException

提供的 TTL 不在 0 到 255 之間

ObjectDisposedException

基礎 Socket 已關閉。

SocketException

存取套接字時發生錯誤。

ArgumentNullException

multicastAddr null。

ArgumentException

IP 位址與定義套接字尋址配置的 AddressFamily 值不相容。

範例

下列範例示範如何藉由提供兩個參數、多播位址和代表TTL的數位來聯結多播群組。

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

備註

JoinMulticastGroup 方法會使用指定的 IPAddress，將 UdpClient 訂閱至多播群組。呼叫 JoinMulticastGroup 方法之後，基礎 Socket 會將因特網群組管理通訊協定（IGMP）封包傳送至要求多播群組成員資格的路由器。多播位址範圍是 224.0.0.0 到 239.255.255.255。如果您指定超出此範圍的位址，或提出要求的路由器未啟用多播，UdpClient 會擲回 SocketException。如果您收到 SocketException，請使用 SocketException.ErrorCode 取得特定的錯誤碼。取得此程式代碼之後，您可以參閱 Windows Sockets 第 2 版 API 錯誤碼檔，以取得錯誤的詳細描述。 timeToLive 參數會指定在捨棄多播數據報之前，將允許多少路由器躍點。一旦將路由器列為多播群組成員的 UdpClient，它就能夠接收傳送至指定之 IPAddress的多播數據報。

注意

您必須使用多播埠號碼建立 UdpClient，否則您將無法接收多播數據報。在呼叫 JoinMulticastGroup 方法之前，請勿呼叫 Connect 方法，否則接收方法將無法運作。您不需要屬於多播群組，即可將數據報傳送至多播IP位址。

加入多播群組之前，請確定套接字已系結至埠或端點。您可以呼叫其中一個接受做為埠或端點參數的建構函式來執行此動作。

若要停止接收多播數據報，請呼叫 DropMulticastGroup 方法，並提供您想要從中撤銷的群組 IPAddress。

注意

您無法在沒有特定本機埠的情況下，在建構 UdpClient 上呼叫 JoinMulticastGroup（也就是使用 UdpClient() 或 UdpClient(AddressFamily) 建構函式）。

另請參閱

DropMulticastGroup(IPAddress)

適用於

JoinMulticastGroup(IPAddress, IPAddress)

來源:: UDPClient.cs

來源:: UDPClient.cs

來源:: UDPClient.cs

將 UdpClient 新增至多播群組。

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)

參數

multicastAddr: IPAddress

您想要加入之群組的多播 IPAddress。

localAddress: IPAddress

本機 IPAddress。

例外狀況

ObjectDisposedException

基礎 Socket 已關閉。

SocketException

存取套接字時發生錯誤。

範例

下列程式代碼範例示範如何使用 JoinMulticastGroup 方法。

// 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]);
}

備註

加入多播群組之前，請確定套接字系結至埠或端點。您可以呼叫其中一個接受埠或連接點做為參數的建構函式來執行此動作。

注意

有數個多播位址範圍可供選擇。您可以在 IETF RFC 2375 中找到它們。

注意

您無法在沒有特定本機埠的情況下，在建構 UdpClient 上呼叫 JoinMulticastGroup（也就是使用 UdpClient() 或 UdpClient(AddressFamily) 建構函式）。

適用於

共用方式為

UdpClient.JoinMulticastGroup 方法

定義

多載

JoinMulticastGroup(IPAddress)

參數

例外狀況

範例

備註

另請參閱

適用於

JoinMulticastGroup(Int32, IPAddress)

參數

例外狀況

範例

備註

適用於

JoinMulticastGroup(IPAddress, Int32)

參數

例外狀況

範例

備註

另請參閱

適用於

JoinMulticastGroup(IPAddress, IPAddress)

參數

例外狀況

範例

備註

適用於

其他資源