Question

我正在尝试读取连续的UDP字节（或者一次至少读取1个以上）。我的缓冲区大小是单个数据报/数据包（1000字节）的4倍。

 Byte[] receiveBytes = new Byte[4096];

 UdpClient udpClient = new UdpClient(56885);
 IPEndPoint RemoteIpEndPoint = new IPEndPoint(IPAddress.Any, 0);
 Byte[] receiveBytes = udpClient.Receive(ref RemoteIpEndPoint);

Answer 1

Receive method一次只能读取一个数据报包。如果您想要阅读多个数据报，则需要多次调用Receive。

Answer 2

如果要接收多个数据包，则应考虑使用异步方法接收它们。 UdpClient类有一个异步惯用法，你给它一个回调函数，然后继续进行其他处理（比如更新UI）。

Here is an example from the source:

public static bool messageReceived = false;

public static void ReceiveCallback(IAsyncResult ar)
{
  UdpClient u = (UdpClient)((UdpState)(ar.AsyncState)).u;
  IPEndPoint e = (IPEndPoint)((UdpState)(ar.AsyncState)).e;

  Byte[] receiveBytes = u.EndReceive(ar, ref e);
  string receiveString = Encoding.ASCII.GetString(receiveBytes);

  Console.WriteLine("Received: {0}", receiveString);
  messageReceived = true;
}

public static void ReceiveMessages()
{
  // Receive a message and write it to the console.
  IPEndPoint e = new IPEndPoint(IPAddress.Any, listenPort);
  UdpClient u = new UdpClient(e);

  UdpState s = new UdpState();
  s.e = e;
  s.u = u;

  Console.WriteLine("listening for messages");
  u.BeginReceive(new AsyncCallback(ReceiveCallback), s);

  // Do some work while we wait for a message. For this example, 
  // we'll just sleep 
  while (!messageReceived)
  {
    Thread.Sleep(100);
  }
}

UDPClient只接收一个数据报

2 个答案: