/** 实现一个 ASM 信道（即 ASM 帮助类），供外部调用* * * 通过 UdpAnySourceMulticastClient 实现 ASM（Any Source Multicast），即“任意源多播”* 多播组基于 IGMP（Internet Group Management Protocol），即“Internet组管理协议”* * UdpAnySourceMulticastClient - 一个发送信息到多播组并从任意源接收多播信息的客户端，即 ASM 客户端*     BeginJoinGroup(), EndJoinGroup() - 加入多播组的异步方法*     BeginReceiveFromGroup(), EndReceiveFromGroup() - 从多播组接收信息的异步方法（可以理解为接收多播组内所有成员发送的信息）*     BeginSendToGroup(), EndSendToGroup() - 发送信息到多播组的异步方法（可以理解为发送信息到多播组内的全部成员）*     ReceiveBufferSize - 接收信息的缓冲区大小*     SendBufferSize - 发送信息的缓冲区大小*     *     BeginSendTo(), EndSendTo() - 发送信息到指定目标的异步方法*     BlockSource() - 阻止指定源，以便不再接收该源发来的信息*     UnblockSource() - 取消阻止指定源*     MulticastLoopback - 发出的信息是否需要传给自己* */using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;using System.Text;
using System.Net.Sockets;namespace Demo.Communication.SocketClient
{public class UdpAnySourceMulticastChannel : IDisposable{// ASM 客户端private UdpAnySourceMulticastClient _client;// 接收信息的缓冲区private byte[] _buffer;// 此客户端是否加入了多播组private bool _isJoined;/// <summary>/// 构造函数/// </summary>/// <param name="groupAddress">多播组地址</param>/// <param name="port">多播组的端口</param>/// <param name="maxMessageSize">接收信息的缓冲区大小</param>/// <remarks>/// 注：udp 报文（Datagram）的最大长度为 65535（包括报文头）/// </remarks>public UdpAnySourceMulticastChannel(IPAddress groupAddress, int port, int maxMessageSize){_buffer = new byte[maxMessageSize];// 实例化 ASM 客户端，需要指定的参数为：多播组地址；多播组的端口_client = new UdpAnySourceMulticastClient(groupAddress, port);}// 收到多播信息后触发的事件public event EventHandler<UdpPacketEventArgs> Received;private void OnReceived(IPEndPoint source, byte[] data){var handler = Received;if (handler != null)handler(this, new UdpPacketEventArgs(data, source));}// 加入多播组后触发的事件public event EventHandler Opening;private void OnOpening(){var handler = Opening;if (handler != null)handler(this, EventArgs.Empty);}// 断开多播组后触发的事件public event EventHandler Closing;private void OnClosing(){var handler = Closing;if (handler != null)handler(this, EventArgs.Empty);}/// <summary>/// 加入多播组/// </summary>public void Open(){if (!_isJoined){_client.BeginJoinGroup(result =>{_client.EndJoinGroup(result);_isJoined = true;Deployment.Current.Dispatcher.BeginInvoke(() =>{OnOpening();Receive();});}, null);}}/// <summary>/// 发送信息到多播组，即发送信息到多播组内的所有成员/// </summary>public void Send(string msg){if (_isJoined){byte[] data = Encoding.UTF8.GetBytes(msg);_client.BeginSendToGroup(data, 0, data.Length,result =>{_client.EndSendToGroup(result);}, null);}}/// <summary>/// 从多播组接收信息，即接收多播组内所有成员发送的信息/// </summary>private void Receive(){if (_isJoined){Array.Clear(_buffer, 0, _buffer.Length);_client.BeginReceiveFromGroup(_buffer, 0, _buffer.Length,result =>{IPEndPoint source;_client.EndReceiveFromGroup(result, out source);Deployment.Current.Dispatcher.BeginInvoke(() =>{OnReceived(source, _buffer);Receive();});}, null);}}// 关闭 ASM 信道public void Close(){_isJoined = false;OnClosing();Dispose();}public void Dispose(){if (_client != null)_client.Dispose();}}
}

<phone:PhoneApplicationPage x:Class="Demo.Communication.SocketClient.AnySourceMulticast"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"xmlns:d="http://schemas.microsoft.com/expression/blend/2008"xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"FontFamily="{StaticResource PhoneFontFamilyNormal}"FontSize="{StaticResource PhoneFontSizeNormal}"Foreground="{StaticResource PhoneForegroundBrush}"SupportedOrientations="Portrait" Orientation="Portrait"mc:Ignorable="d" d:DesignHeight="768" d:DesignWidth="480"shell:SystemTray.IsVisible="True"><Grid x:Name="LayoutRoot" Background="Transparent"><StackPanel HorizontalAlignment="Left"><ListBox Name="lstAllMsg" MaxHeight="400" /><TextBox x:Name="txtName" /><TextBox x:Name="txtInput" KeyDown="txtInput_KeyDown" /><Button x:Name="btnSend" Content="发送" Click="btnSend_Click" /></StackPanel>        </Grid></phone:PhoneApplicationPage>

/** 用于演示 ASM*/using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using Microsoft.Phone.Controls;using System.Windows.Navigation;namespace Demo.Communication.SocketClient
{public partial class AnySourceMulticast : PhoneApplicationPage{// 实例化自定义的 ASM 信道private UdpAnySourceMulticastChannel _channel;public AnySourceMulticast(){InitializeComponent();}protected override void OnNavigatedTo(NavigationEventArgs e){txtName.Text = "匿名" + new Random().Next(1000, 9999).ToString();// 多播组地址是必须介于 224.0.0.0 到 239.255.255.255 之间的 IP 地址，其中范围介于 224.0.0.0 到 224.0.0.255 之间的多播地址是保留多播地址// 比如：224.0.0.0 是基址，224.0.0.1 是代表同一个物理网络中所有系统的多播组地址，而 224.0.0.2 代表同一个物理网络中的所有路由器_channel = new UdpAnySourceMulticastChannel(IPAddress.Parse("224.0.1.1"), 3368, 2048); _channel.Opening += new EventHandler(_channel_Opening);_channel.Received += new EventHandler<UdpPacketEventArgs>(_channel_Received);_channel.Closing += new EventHandler(_channel_Closing);_channel.Open();// 需要的使用，应该调用 Close()// _channel.Close();
        }void _channel_Opening(object sender, EventArgs e){_channel.Send(string.Format("{0}: 进来了 - [{1}]", txtName.Text, DateTime.Now.ToString("HH:mm:ss")));}void _channel_Received(object sender, UdpPacketEventArgs e){// 因为已经指定了接收信息的缓冲区大小是 2048 ，所以如果信息不够 2048 个字节的的话，空白处均为空字节“\0”string message = string.Format("{0} - 来自：{1}", e.Message.TrimEnd('\0'), e.Source.ToString()); lstAllMsg.Items.Insert(0, message); }void _channel_Closing(object sender, EventArgs e){_channel.Send(string.Format("{0}: 离开了 - [{1}]", txtName.Text, DateTime.Now.ToString("HH:mm:ss")));}private void btnSend_Click(object sender, RoutedEventArgs e){SendMsg();}private void txtInput_KeyDown(object sender, KeyEventArgs e){if (e.Key == Key.Enter){SendMsg();this.Focus();}}private void SendMsg(){_channel.Send(string.Format("{0}: {1} - [{2}]", txtName.Text, txtInput.Text, DateTime.Now.ToString("HH:mm:ss")));txtInput.Text = "";}}
}