Socket communication C#

我使用这个类从/发送Echo测试到我的应用程序

public class SocketClient
{
    Socket socket = null;
    static ManualResetEvent clientDone = new ManualResetEvent(false);
    const int TIMEOUT_MILLISECONDS = 5000;
    const int MAX_BUFFER_SIZE = 2048;
    public SocketClient()
    {
        socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
    }
    public string Send(string serverName, int portNumber, string data)
    {
        string response = "Timeout";
        if (socket != null)
        {
            SocketAsyncEventArgs socketEventArg = new SocketAsyncEventArgs();
            socketEventArg.RemoteEndPoint = new DnsEndPoint(serverName, portNumber);
            socketEventArg.Completed += new EventHandler<SocketAsyncEventArgs>(delegate(object s, SocketAsyncEventArgs e)
            {
                response = e.SocketError.ToString();
                clientDone.Set();
            });
            byte[] payload = Encoding.UTF8.GetBytes(data);
            socketEventArg.SetBuffer(payload, 0, payload.Length);
            clientDone.Reset();
            socket.SendToAsync(socketEventArg);
            clientDone.WaitOne(TIMEOUT_MILLISECONDS);
        }
        else
        {
            response = "not initialized";
        }
        return response;
    }
    public string Recieve(int portNumber)
    {
        string response = "Timeout";
        if (socket != null)
        {
            SocketAsyncEventArgs socketEventArg = new SocketAsyncEventArgs();
            socketEventArg.SetBuffer(new Byte[MAX_BUFFER_SIZE], 0, MAX_BUFFER_SIZE);
            socketEventArg.Completed += new EventHandler<SocketAsyncEventArgs>(delegate(object s, SocketAsyncEventArgs e)
            {
                if (e.SocketError == SocketError.Success)
                {
                    response = Encoding.UTF8.GetString(e.Buffer, e.Offset, e.BytesTransferred);
                    response.Trim(''0');
                }
                else
                {
                    response = e.SocketError.ToString();
                }
                clientDone.Set();
            });
            socketEventArg.RemoteEndPoint = new IPEndPoint(IPAddress.Any, portNumber);
            clientDone.Reset();
            socket.ReceiveFromAsync(socketEventArg);
            clientDone.WaitOne(TIMEOUT_MILLISECONDS);
        }
        return response;
    }
    public void Close()
    {
        socket.Close();
    }
}

，下面是我的用法:

        SocketClient client = new SocketClient();
        client.Send("192.168.1.2",77 , "besm ellah");
        textBox1.Text=client.Recieve(77);

它总是通过参数异常在socket.SendToAsync(socketEventArg);未处理"参数remoteEP不能是DnsEndPoint类型。"参数名称:remoteEP"

我在windows功能上启用了简单的TCP/IP功能，但它也不起作用。

- update -

我试着把代码改成:

IPAddress[] localIPs = Dns.GetHostAddresses(Dns.GetHostName());
socketEventArg.RemoteEndPoint = new IPEndPoint(localIPs[3], portNumber);

它没有给出异常，但是消息没有通过。