对,希望快速提问和回答 . 我的应用程序应该监听UDP端口和某个showcontrol服务器的任何IP地址 . 它只发送纯ASCII文本/字符串 .
由于我们办公室没有这样的S.C.服务器,我还写了一个非常小的简单控制台应用程序,只是广播UDP数据包 .
这是控制台应用程序:
static void Main(string[] args)
{
Thread.Sleep(1000);
Socket soc = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
IPEndPoint e = new IPEndPoint(IPAddress.Broadcast, 35000);
IPAddress broadcast = IPAddress.Parse("192.168.1.255");
e = new IPEndPoint(broadcast, 35000);
string s;
Byte[] sendBytes;
while ("exit" != (s = Console.ReadLine()))
{
sendBytes = Encoding.ASCII.GetBytes((s.EndsWith("\n") ? s : s + "\n"));
soc.SendTo(sendBytes, e);
}
sendBytes = Encoding.ASCII.GetBytes("EXIT\n");
soc.SendTo(sendBytes, e);
soc.Close();
}
我在听众部分尝试了两件事 . 使用UdpClient并使用套接字连接,两者都给了我完全相同的问题,我将在下面的两个监听器代码中描述:
套接字版本:
public MediaPlayer(Output outputWindow)
{
Socket serverSocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
IPEndPoint ipEndPoint = new IPEndPoint(IPAddress.Any, i_inPort);
serverSocket.Bind(ipEndPoint);
IPEndPoint ipeSender = new IPEndPoint(IPAddress.Any, 0);
EndPoint epSender = (EndPoint)ipeSender;
SocketState state = new SocketState();
state.e = epSender;
state.s = serverSocket;
beginReceiveFrom(state);
}
public void beginReceiveFrom(SocketState state)
{
state.byteData = new byte[state.byteData.Length];
IPEndPoint ipeSender = new IPEndPoint(IPAddress.Any, 0);
state.e = (EndPoint)ipeSender;
state.s.BeginReceiveFrom(state.byteData, 0, state.byteData.Length, SocketFlags.None, ref state.e, onReceiveFrom, state);
}
public void onReceiveFrom(IAsyncResult ar)
{
SocketState state = (SocketState)ar.AsyncState;
Socket serverSocket = state.s;
//EndPoint epSender = state.e;
IPEndPoint ipeSender = new IPEndPoint(IPAddress.Any, 0);
EndPoint epSender = (EndPoint)ipeSender;
try
{
serverSocket.EndReceiveFrom(ar, ref epSender);
string s = Encoding.ASCII.GetString(state.byteData);
}
catch (System.Exception ex)
{
Console.WriteLine(ex);
}
finally
{
beginReceiveFrom(state);
}
}
UdpClient版本:
public MediaPlayer(Output outputWindow)
{
UdpClient client = new UdpClient(i_inPort);
IPEndPoint endPoint = null;
UdpState state = new UdpState();
state.e = endPoint;
state.u = client;
}
private void BeginReceive(UdpState state)
{
state.u.BeginReceive(new AsyncCallback(ReceiveCallback), state);
}
private void ReceiveCallback(IAsyncResult ar)
{
UdpState state = null;
try
{
state = (UdpState)ar.AsyncState;
Byte[] receiveBytes = state.u.EndReceive(ar, ref state.e);
string receiveString = Encoding.ASCII.GetString(receiveBytes);
executive.Receive(receiveString);
BeginReceive(state);
}
catch(System.Exception ex)
{
SetText(ex.ToString());
}
}
UpdClient ReceiveCallback版本中有一些额外的代码,因为这是我最初使用的代码 . 问题是,当我在我的公司网络和任何计算机上发送/播放控制台应用程序时,它只是工作,没问题 . 多个媒体播放器可以在任何数量的计算机上播放而没有任何问题 .
但是,当我使用不同的UDP发送器(类似于来自hw-group.com的Hercules)时,它根本无法工作,>直到<我用我的控制台应用程序发送一个命令 . 只有这样,在我的控制台应用程序发送文本/数据包/数据后,我的applcation才会接受来自hercules应用程序的数据 .
有没有人看到我做错了什么?我已经阅读了多个代码示例,从这里,codeproject和guru-something,它们都使用了我使用的相同类型的编程 .
此外,抱歉文本墙 .
1 回答
可能是您发送到设备的消息中不存在的数据包的标头,请仔细检查并确保消息正确解码 .