广播UDP消息到所有可用的网络卡(Broadcasting UDP message to all t

我需要发送一个UDP信息到指定的IP和端口。

由于有3个网卡，

10.1.x.x
10.2.x.x
10.4.x.x

当我发送一个UDP消息，我只在一个网络适配器接收的消息......在IP的其余部分都没有收到。

我要检查网络适配器同时发送消息。我怎样才能做到这一点？

目前我使用下列内容：

IPEndPoint localEndPoint = new IPEndPoint(IPAddress.Parse(LocalIP), 0);
IPEndPoint targetEndPoint = new IPEndPoint(TargetIP, iTargetPort);
UdpClient sendUdpClient = new UdpClient(localEndPoint);
int numBytesSent = sendUdpClient.Send(CombineHeaderBody, CombineHeaderBody.Length, targetEndPoint);

Answer 1:

这实际上比听上去还要棘手，因为如果你有多个接口的广播将不会经常出去到所有的接口。为了解决这个问题，我创建这个类。

public class MyUdpClient : UdpClient
{
   public MyUdpClient() : base()
   {
      //Calls the protected Client property belonging to the UdpClient base class.
      Socket s = this.Client;
      //Uses the Socket returned by Client to set an option that is not available using UdpClient.
      s.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.Broadcast, 1);
      s.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.DontRoute, 1);
   }

   public MyUdpClient(IPEndPoint ipLocalEndPoint) : base(ipLocalEndPoint)
   {
      //Calls the protected Client property belonging to the UdpClient base class.
      Socket s = this.Client;
      //Uses the Socket returned by Client to set an option that is not available using UdpClient.
      s.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.Broadcast, 1);
      s.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.DontRoute, 1);
   }

}

然后通过广播发送UDP数据包，我用像下面这样。我使用IPAddress.Broadcast和MyUdpClient ，这是从您的代码不同。

IPEndPoint  localEndPoint  = new IPEndPoint(IPAddress.Parse(LocalIP), 0);
IPEndPoint  targetEndPoint = new IPEndPoint(IPAddress.Broadcast, iTargetPort);
MyUdpClient sendUdpClient  = new MyUdpClient(localEndPoint);
int numBytesSent = sendUdpClient.Send(CombineHeaderBody, CombineHeaderBody.Length, targetEndPoint);

此外，你应该注意，当您使用特定的ipaddress ，而不是广播的路由表只发送它的地址相匹配的接口。

因此，在您的例子中，使用单播。您需要设置LocalIP您要发送给本地接口的IP。有三个接口，您将有三个本地IP的，你需要选择正确的使用。

IPEndPoint  localEndPoint  = new IPEndPoint(IPAddress.Parse(LocalIP), 0);
IPEndPoint  targetEndPoint = new IPEndPoint(TargetIP, iTargetPort);
MyUdpClient sendUdpClient  = new MyUdpClient(localEndPoint);
int numBytesSent = sendUdpClient.Send(CombineHeaderBody, CombineHeaderBody.Length, targetEndPoint);

由于路径被关闭，你可能会看到它的所有接口，但你将需要测试本作的单播情况。

如果你不关心发送IP或端口，你可以使用下面的代码。

IPEndPoint  targetEndPoint = new IPEndPoint(TargetIP, iTargetPort);
MyUdpClient sendUdpClient  = new MyUdpClient();
int numBytesSent = sendUdpClient.Send(CombineHeaderBody, CombineHeaderBody.Length, targetEndPoint);

或广播

IPEndPoint  targetEndPoint = new IPEndPoint(IPAddress.Broadcast, iTargetPort);
MyUdpClient sendUdpClient  = new MyUdpClient();
int numBytesSent = sendUdpClient.Send(CombineHeaderBody, CombineHeaderBody.Length, targetEndPoint);

这个问题IPAddress.Broadcast是，他们将不通过任何网关路由。为了解决这个问题，你可以创建一个列表IPAddresses通过，然后循环和发送。此外，由于发送可能会失败，你无法控制你也应该有一个try / catch块的网络问题。

ArrayList ip_addr_acq = new ArrayList();

ip_addr_acq.Add(IPAddress.Parse("10.1.1.1")); // add to list of address to send to

try
{
   foreach (IPAddress curAdd in ip_addr_acq) 
   {
       IPEndPoint  targetEndPoint = new IPEndPoint(curAdd , iTargetPort);
       MyUdpClient sendUdpClient  = new MyUdpClient();
       int numBytesSent = sendUdpClient.Send(CombineHeaderBody, CombineHeaderBody.Length, targetEndPoint);

       Thread.Sleep(40); //small delay between each message
    }
 }
 catch
 {
 // handle any exceptions
 }

编辑：见上述变化具有多个接口，并且还以单播问题试图单播数据包到可用网络。

Answer 2:

雷克斯的答案扩展。这可以让你不必硬编码要播出的IP地址。遍历所有的接口，检查是否他们都在涨，确保它具有IPv4的信息，以及IPv4地址与它关联。只是改变了“数据”变量任何数据要播了，“目标”端口，一个你想要的。小缺点是，如果接口有多个与之相关的IP地址，它会广播出每个地址。注意：这也将尝试通过任何VPN适配器发送广播（通过网络和共享中心/网络连接，赢7+验证），如果你想接收响应，你必须保存所有的客户。你也将不再需要二级类。

    foreach( NetworkInterface ni in NetworkInterface.GetAllNetworkInterfaces() ) {
        if( ni.OperationalStatus == OperationalStatus.Up && ni.SupportsMulticast && ni.GetIPProperties().GetIPv4Properties() != null ) {
            int id = ni.GetIPProperties().GetIPv4Properties().Index;
            if( NetworkInterface.LoopbackInterfaceIndex != id ) {
                foreach(UnicastIPAddressInformation uip in ni.GetIPProperties().UnicastAddresses ) {
                    if( uip.Address.AddressFamily == AddressFamily.InterNetwork ) {
                        IPEndPoint local = new IPEndPoint(uip.Address.Address, 0);
                        UdpClient udpc = new UdpClient(local);
                        udpc.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.Broadcast, 1);
                        udpc.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.DontRoute, 1);
                        byte[] data = new byte[10]{1,2,3,4,5,6,7,8,9,10};
                        IPEndPoint target = new IPEndPoint(IPAddress.Broadcast, 48888);
                        udpc.Send(data,data.Length, target);
                    }
                }
            }
        }
    }

Answer 3:

我通过（使用绑定）从每个适配器发送UDP广播解决了这个问题：

public static void SNCT_SendBroadcast(out List<MyDevice> DevicesList)
{
DevicesList = new List<MyDevice>();
byte[] data = new byte[2]; //broadcast data
data[0] = 0x0A;
data[1] = 0x60;

IPEndPoint ip = new IPEndPoint(IPAddress.Broadcast, 45000); //braodcast IP address, and corresponding port

NetworkInterface[] nics = System.Net.NetworkInformation.NetworkInterface.GetAllNetworkInterfaces(); //get all network interfaces of the computer

foreach (NetworkInterface adapter in nics)
{
// Only select interfaces that are Ethernet type and support IPv4 (important to minimize waiting time)
if (adapter.NetworkInterfaceType != NetworkInterfaceType.Ethernet) { continue; }
if (adapter.Supports(NetworkInterfaceComponent.IPv4) == false) { continue; }
try
{
    IPInterfaceProperties adapterProperties = adapter.GetIPProperties();    
    foreach (var ua in adapterProperties.UnicastAddresses)
    {
        if (ua.Address.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork)
        {
         //SEND BROADCAST IN THE ADAPTER
            //1) Set the socket as UDP Client
            Socket bcSocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp); //broadcast socket
            //2) Set socker options
            bcSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.Broadcast, 1);
            bcSocket.ReceiveTimeout = 200; //receive timout 200ms
            //3) Bind to the current selected adapter
            IPEndPoint myLocalEndPoint = new IPEndPoint(ua.Address, 45000);
            bcSocket.Bind(myLocalEndPoint);
            //4) Send the broadcast data
            bcSocket.SendTo(data, ip);

        //RECEIVE BROADCAST IN THE ADAPTER
            int BUFFER_SIZE_ANSWER = 1024;
            byte[] bufferAnswer = new byte[BUFFER_SIZE_ANSWER];
            do
            {
                try
                {
                    bcSocket.Receive(bufferAnswer);
                    DevicesList.Add(GetMyDevice(bufferAnswer)); //Corresponding functions to get the devices information. Depends on the application.
                }
                catch { break; }

            } while (bcSocket.ReceiveTimeout != 0); //fixed receive timeout for each adapter that supports our broadcast
            bcSocket.Close();
        }
    }
  }
  catch { }
}
return;
}