重复消息，但不应在任务中重复此消息

Question

看图片中的问题。服务器启动一个新的任务来接受客户端，然后在函数句柄（客户端）中处理它，这一切都很好，但是每次它重复这个消息“客户端正在连接......”，但它不应该。除了这条消息之外，没有其他任务被调用。并且 bool Pending() 是假的，所以它不应该启动另一个任务。

using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace WebServer
{
    class WebServer
    {
        public static WebServer Server { get; private set; }

        private TcpListener _tcpListener = null;
        public CancellationTokenSource TokenSource { get; private set; }
        public CancellationToken Token { get; private set; }

        public int i = 0;

        static void Main(string[] args)
        {
            WebServer.Server = new WebServer();
        }

        WebServer()
        {
            IPAddress ipAddress;

            try
            {
                ipAddress = IPAddress.Parse("127.0.0.1");
            } catch(Exception e)
            {
                Console.WriteLine("Error while parsing ip address: " + e.Message);
                return;
            }

            _tcpListener = new TcpListener(ipAddress, 8080);
            _tcpListener.Start();

            TokenSource = new CancellationTokenSource();
            Token = TokenSource.Token;

            //Execute server
            Task.Run(() => Run());

            Console.ReadKey();
            TokenSource.Cancel();

            WaitHandle handle = Token.WaitHandle;
            handle.WaitOne();
        }

        private void Run()
        {
            Console.WriteLine("Server is runnning");
            while(!Token.IsCancellationRequested)
            {
                if(_tcpListener.Pending())
                {
                    Console.WriteLine("Pending: " + _tcpListener.Pending());
                    Task.Run(() => {
                        Console.WriteLine("Client connecting...");
                        TcpClient client = _tcpListener.AcceptTcpClient();

                        this.Handle(client);
                        return;
                    });
                }
            }
        }

        private void Handle(TcpClient client)
        {
            NetworkStream stream = client.GetStream();

            Console.WriteLine("Handling....");

            while(client.Connected)
            {
                if(stream.DataAvailable)
                {
                    Console.WriteLine("Start Reading...");
                    byte[] buffer = new byte[1024];
                    stream.Read(buffer, 0, 1024);
                    Console.WriteLine("Read: " + Encoding.ASCII.GetString(buffer));
                }

                client.Close();
            }
        }
    }
}

客户端连接不应每次都重复，其他一切正常

Answer 1

Emrah Süngü 的 cmets 似乎准确无误

TcpClient client = _tcpListener.AcceptTcpClient(); // accept first
Console.WriteLine("Client connecting...");

// then start processing in your task
Task.Run(() => this.Handle(client));

仔细想想，这很有意义，您正处于一个 while 循环中，并且您在代码实际运行之前启动了几个任务。

免责声明：这是完全未经测试的，我不对您使用此代码对他人或您自己造成的伤害负责：)