C#模拟http服务器响应post请求但是没有收到数据

Question

我启动本地服务器时可以正常接收到post过来的数据，上传到阿里云启动外网服务器之后就收不到了

处理接收的代码，业务逻辑已经注释，在接收到数据时立即调用Messagebox.Show()来显示接收到的字符串（别纠结用winform做的……）

private void handleTheRequest(Socket clientSocket)
{
    if (clientSocket.Available <= 0)
        return;
    byte[] buffer = new byte[4096]; 
    int receivedBCount = clientSocket.Receive(buffer); // Receive the request
    string strReceived = charEncoder.GetString(buffer, 0, receivedBCount);
    MessageBox.Show(strReceived);
}

启动服务器的代码

public bool start(IPAddress ipAddress, int port, int maxNOfCon, string contentPath)
{
    if (running) return false; // If it is already running, exit.

    try
    {
        if (serverSocket != null)
            serverSocket.Close();
        // A tcp/ip socket (ipv4)
        serverSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream,
            ProtocolType.Tcp);
        serverSocket.Bind(new IPEndPoint(IPAddress.Any, port));
        serverSocket.Listen(maxNOfCon);
        serverSocket.ReceiveTimeout = timeout;
        serverSocket.SendTimeout = timeout;
        running = true;
        this.contentPath = contentPath;
    }
    catch (Exception _e)
    {
        form.DoLog(_e.ToString());
        return false;
    }

    form.DoLog("Server running at port: " + port);
    // Our thread that will listen connection requests
    // and create new threads to handle them.
    Thread requestListenerT = new Thread(() =>
    {
        while (running)
        {
            Socket clientSocket;
            try
            {
                clientSocket = serverSocket.Accept();
                // Create new thread to handle the request and continue to listen the socket.
                Thread requestHandler = new Thread(() =>
                {
                    clientSocket.ReceiveTimeout = timeout;
                    clientSocket.SendTimeout = timeout;
                    try
                    {
                        handleTheRequest(clientSocket);
                    }
                    catch (Exception _e)
                    {
                        try
                        {
                            form.DoLog(_e.ToString());
                            clientSocket.Close();
                        }
                        catch
                        {
                        }
                    }
                });
                requestHandler.Start();
            }
            catch (Exception _e)
            {
                form.DoLog("【】" + _e.ToString());
            }
        }
    });
    requestListenerT.Start();

    return true;
}

附图，第一张是本地服务器接收到的数据内容，第二张是外网服务器接收到的内容