UdpClient.JoinMulticastGroup 方法

参考

定义

命名空间:: System.Net.Sockets

程序集:: System.Net.Sockets.dll

程序集:: System.dll

程序集:: netstandard.dll

重要

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将 UdpClient 添加到多播组。

重载

JoinMulticastGroup(IPAddress)	将 UdpClient 添加到多播组。
JoinMulticastGroup(Int32, IPAddress)	将 UdpClient 添加到多播组。
JoinMulticastGroup(IPAddress, Int32)	将 UdpClient 添加到具有指定生存时间 (TTL) 的多播组。
JoinMulticastGroup(IPAddress, IPAddress)	将 UdpClient 添加到多播组。

JoinMulticastGroup(IPAddress)

Source:: UDPClient.cs

Source:: UDPClient.cs

Source:: UDPClient.cs

将 UdpClient 添加到多播组。

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)

参数

multicastAddr: IPAddress

要加入的组的多播 IPAddress。

例外

ObjectDisposedException

已关闭基础 Socket。

SocketException

访问套接字时出错。

ArgumentException

IP 地址与定义套接字的寻址方案所用的 AddressFamily 值不相符。

示例

下面的代码示例演示如何通过提供多播地址加入多播组。

#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

注解

方法JoinMulticastGroup使用指定的 IPAddress将订阅UdpClient到多播组。调用 JoinMulticastGroup 方法后，基础 Socket 将 Internet 组管理协议 (IGMP) 数据包发送到请求加入多播组的路由器。多播地址范围为 224.0.0.0 到 239.255.255.255。如果指定此范围之外的地址，或者发出请求的路由器未启用多播， UdpClient 将引发 SocketException。如果收到 SocketException，请使用 SocketException.ErrorCode 获取特定的错误代码。获取此代码后，可以参阅 Windows 套接字版本 2 API 错误代码文档，获取错误的详细说明。将 UdpClient 与路由器一起列为多播组的成员后，它将能够接收发送到指定 IPAddress的多播数据报。

注意

必须使用多播端口号创建 UdpClient ;否则，将无法接收多播数据报。请勿在 Connect 调用方法之前调用 JoinMulticastGroup 方法，否则该方法 Receive 将不起作用。无需属于多播组即可将数据报发送到多播 IP 地址。

在加入多播组之前，请确保套接字绑定到端口或终结点。为此，可以调用接受端口或终结点作为参数的构造函数之一。

若要停止接收多播数据报，请调用 DropMulticastGroup 方法并提供 IPAddress 要从中撤回的组的。

注意

在 IPv6 情况下，可以选择多个多播地址范围。请参阅 IETF RFC 2375。

注意

不能在UdpClient没有特定本地端口 (构造的上调用 JoinMulticastGroup ，即使用 UdpClient() 或 UdpClient(AddressFamily) 构造函数) 。

另请参阅

DropMulticastGroup(IPAddress)

适用于

JoinMulticastGroup(Int32, IPAddress)

Source:: UDPClient.cs

Source:: UDPClient.cs

Source:: UDPClient.cs

将 UdpClient 添加到多播组。

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)

参数

ifindex: Int32

与在其上加入多播组的本地 IP 地址关联的接口索引。

multicastAddr: IPAddress

要加入的组的多播 IPAddress。

例外

ObjectDisposedException

已关闭基础 Socket。

SocketException

访问套接字时出错。

示例

// 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)

注解

在加入多播组之前，请确保套接字已绑定到端口或终结点。为此，可以调用接受端口或终结点作为参数的构造函数之一。

参数 infindex 用于标识同一链接上的硬件接口。

注意

有多种多播地址范围可供选择。请参阅 IETF RFC 2375。

注意

不能在UdpClient没有特定本地端口 (构造的上调用 JoinMulticastGroup ，即使用 UdpClient.UdpClient() 或 UdpClient.UdpClient(AddressFamily) 构造函数) 。

适用于

JoinMulticastGroup(IPAddress, Int32)

Source:: UDPClient.cs

Source:: UDPClient.cs

Source:: UDPClient.cs

将 UdpClient 添加到具有指定生存时间 (TTL) 的多播组。

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)

参数

multicastAddr: IPAddress

要加入的多播组的 IPAddress。

timeToLive: Int32

生存时间 (TTL)，以路由器跃点数为单位。

例外

ArgumentOutOfRangeException

所提供的 TTL 不在 0 和 255 之间

ObjectDisposedException

已关闭基础 Socket。

SocketException

访问套接字时出错。

ArgumentNullException

multicastAddr 为 null。

ArgumentException

IP 地址与定义套接字的寻址方案所用的 AddressFamily 值不相符。

示例

以下示例演示如何通过提供两个参数（一个多播地址）和一个表示 TTL 的数字来联接多播组。

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

注解

方法JoinMulticastGroup使用指定的 IPAddress将订阅UdpClient到多播组。调用 JoinMulticastGroup 方法后，基础 Socket 将 Internet 组管理协议 (IGMP) 数据包发送到请求加入多播组的路由器。多播地址范围为 224.0.0.0 到 239.255.255.255。如果指定此范围之外的地址，或者发出请求的路由器未启用多播， UdpClient 将引发 SocketException。如果收到 SocketException，请使用 SocketException.ErrorCode 获取特定的错误代码。获取此代码后，可以参阅 Windows 套接字版本 2 API 错误代码文档，获取错误的详细说明。参数 timeToLive 指定在放弃多播数据报之前允许的路由器跃点数。将 UdpClient 与路由器一起列为多播组的成员后，它将能够接收发送到指定 IPAddress的多播数据报。

注意

必须使用多播端口号创建 UdpClient ，否则将无法接收多播数据报。请勿在 Connect 调用方法之前调用方法， JoinMulticastGroup 否则接收方法将不起作用。无需属于多播组即可将数据报发送到多播 IP 地址。

在加入多播组之前，请确保套接字绑定到端口或终结点。为此，可以调用接受作为端口或终结点参数的构造函数之一。

若要停止接收多播数据报，请调用 DropMulticastGroup 方法并提供 IPAddress 要从中撤回的组的。

注意

不能在UdpClient没有特定本地端口 (构造的上调用 JoinMulticastGroup ，即使用 UdpClient() 或 UdpClient(AddressFamily) 构造函数) 。

另请参阅

DropMulticastGroup(IPAddress)

适用于

JoinMulticastGroup(IPAddress, IPAddress)

Source:: UDPClient.cs

Source:: UDPClient.cs

Source:: UDPClient.cs

将 UdpClient 添加到多播组。

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)

参数

multicastAddr: IPAddress

要加入的组的多播 IPAddress。

localAddress: IPAddress

本地 IPAddress。

例外

ObjectDisposedException

已关闭基础 Socket。

SocketException

访问套接字时出错。

示例

下面的代码示例演示如何使用 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]);
}

注解

在加入多播组之前，请确保套接字绑定到端口或终结点。为此，可以调用接受端口或终结点作为参数的构造函数之一。

注意

有多种多播地址范围可供选择。可以在 IETF RFC 2375 中找到它们。

注意

不能在UdpClient没有特定本地端口 (构造的上调用 JoinMulticastGroup ，即使用 UdpClient() 或 UdpClient(AddressFamily) 构造函数) 。

适用于

通过

UdpClient.JoinMulticastGroup 方法

定义

重载

JoinMulticastGroup(IPAddress)

参数

例外

示例

注解

另请参阅

适用于

JoinMulticastGroup(Int32, IPAddress)

参数

例外

示例

注解

适用于

JoinMulticastGroup(IPAddress, Int32)

参数

例外

示例

注解

另请参阅

适用于

JoinMulticastGroup(IPAddress, IPAddress)

参数

例外

示例

注解

适用于

其他资源