我需要将UDP消息发送到特定的IP和端口。
由于有3张网卡,
10.1.x.x
10.2.x.x
10.4.x.x
当我发送UDP消息时,我只在一个网络适配器中收到消息...其余的ip都没有收到。
我想在发送邮件时检查网络适配器。我怎么能这样做?
目前我正在使用以下内容:
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);
答案 0 :(得分:16)
这实际上比它听起来更棘手,因为如果你有多个接口,广播将不会总是出现在所有接口上。为了解决这个问题,我创建了这个课程。
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,我使用类似下面的内容。我使用的是IPAddress.Broadcast
和MyUdpClient
,这与您的代码不同。
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);
另外,您应该注意,当您使用特定的ipaddress
而不是广播时,路由表只会将其发送到与该地址匹配的接口。
因此,在您的示例中,使用了单播。您需要将LocalIP
设置为要发送到的本地接口的IP。使用三个接口,您将拥有三个本地IP,您需要选择要使用的正确IP。
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);
由于路由已关闭,您可能会在所有接口上看到它,但您需要针对单播情况对其进行测试。
如果您不关心发送IP或端口,可以使用以下代码。
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);
IPAddress.Broadcast
的问题在于它们不会通过任何网关路由。要解决此问题,您可以创建IPAddresses
列表,然后循环并发送。此外,由于发送可能因您无法控制的网络问题而失败,因此您还应该有一个try / catch块。
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:请参阅上述更改为具有多个界面的单播以及Problem Trying to unicast packets to available networks.
答案 1 :(得分:1)
如果您要发送到特定的IP地址,那么您就是单播,而不是广播。
答案 2 :(得分:1)
扩大雷克斯的答案。这使您无需硬编码要广播的IP地址。循环遍历所有接口,检查它们是否已启动,确保它具有IPv4信息,并且IPv4地址与之关联。只需更改"数据"变量到您要广播的数据,以及" target"端口到你想要的那个。小缺点是如果一个接口有多个与之关联的ip地址,它将从每个地址广播出来。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,Win 7+验证),如果您想接收响应,则必须保存所有客户端。您也不需要二级课程。
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);
}
}
}
}
}
答案 3 :(得分:1)
我通过从每个适配器发送UDP广播解决了这个问题(使用bind):
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;
}