多线程 TCP 服务器和客户端

Question

我只是在问这个问题之前四处搜索，寻找 C# 中的 TCP 服务器和客户端的示例。

我找到了这个链接，我只是使用了链接给出的代码，但不幸的是有一个问题，我被卡住了！

以下代码是服务器（控制台）的完整代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net.Sockets;

namespace TCP_Server_Console
{
    class Program
    {
        static void Main(string[] args)
        {
            TcpListener serverSocket = new TcpListener(8888);
            int requestCount = 0;
            TcpClient clientSocket = default(TcpClient);
            serverSocket.Start();
            Console.WriteLine(" >> Server Started");
            clientSocket = serverSocket.AcceptTcpClient();
            Console.WriteLine(" >> Accept connection from client");
            requestCount = 0;

            while ((true))
            {
                try
                {
                    requestCount = requestCount + 1;
                    NetworkStream networkStream = clientSocket.GetStream();
                    byte[] bytesFrom = new byte[10025];
                    networkStream.Read(bytesFrom, 0, (int)clientSocket.ReceiveBufferSize);
                    string dataFromClient = System.Text.Encoding.ASCII.GetString(bytesFrom);
                    dataFromClient = dataFromClient.Substring(0, dataFromClient.IndexOf("$"));
                    Console.WriteLine(" >> Data from client - " + dataFromClient);
                    string serverResponse = "Last Message from client" + dataFromClient;
                    Byte[] sendBytes = Encoding.ASCII.GetBytes(serverResponse);
                    networkStream.Write(sendBytes, 0, sendBytes.Length);
                    networkStream.Flush();
                    Console.WriteLine(" >> " + serverResponse);
                }
                catch (Exception ex)
                {
                    Console.WriteLine(ex.ToString());
                }
            }

            clientSocket.Close();
            serverSocket.Stop();
            Console.WriteLine(" >> exit");
            Console.ReadLine();
        }
    }
}

/*HandleClient Class */
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Sockets;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace TCP_Server_Console
{
    public class HandleClient
    {
        TcpClient clientSocket;
        string clNo;

        public void startClient(TcpClient inClientSocket, string clineNo)
        {
            this.clientSocket = inClientSocket;
            this.clNo = clineNo;
            Thread ctThread = new Thread(doChat);
            ctThread.Start();
        }

        private void doChat()
        {
            int requestCount = 0;
            byte[] bytesFrom = new byte[10025];
            string dataFromClient = null;
            Byte[] sendBytes = null;
            string serverResponse = null;
            string rCount = null;
            requestCount = 0;

            while ((true))
            {
                try
                {
                    requestCount = requestCount + 1;
                    NetworkStream networkStream = clientSocket.GetStream();
                    networkStream.Read(bytesFrom, 0, (int)clientSocket.ReceiveBufferSize);
                    dataFromClient = System.Text.Encoding.ASCII.GetString(bytesFrom);
                    dataFromClient = dataFromClient.Substring(0, dataFromClient.IndexOf("$"));
                    Console.WriteLine(" >> " + "From client-" + clNo + dataFromClient);
                    rCount = Convert.ToString(requestCount);
                    serverResponse = "Server to clinet(" + clNo + ") " + rCount;
                    sendBytes = Encoding.ASCII.GetBytes(serverResponse);
                    networkStream.Write(sendBytes, 0, sendBytes.Length);
                    networkStream.Flush();
                    Console.WriteLine(" >> " + serverResponse);
                }
                catch (Exception ex)
                {
                    Console.WriteLine(" >> " + ex.ToString());
                }
            }
        }
    }
}

以下代码是客户端（Windows 窗体）的完整代码：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Net.Sockets;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace TCP_Client_Sample
{
    public partial class Form1 : Form
    {
        System.Net.Sockets.TcpClient clientSocket = new System.Net.Sockets.TcpClient();
        NetworkStream serverStream;

        public Form1()
        {
            InitializeComponent();
        }
        private void Form1_Load(object sender, EventArgs e)
        {
            label_status.Text = "Client Started, Connecting...";

            try 
            {
                clientSocket.Connect("127.0.0.1", 8888);

                if (clientSocket.Connected)
                {
                    label_status.Text = "Connected";
                    label_status.ForeColor = Color.Green;
                }
             }
             catch (Exception xe) 
             {
                  MessageBox.Show("OOPS!!! SERVER MUST BE STARTED FIRST! \n\n" + xe.ToString());
             }
        }

        //Function to Send Message to Server (On Button Click)
        private void btn_send_Click(object sender, EventArgs e)
        {
            try 
            {
                NetworkStream serverStream = clientSocket.GetStream();
                byte[] outStream = System.Text.Encoding.ASCII.GetBytes("Message From Client$");
                serverStream.Write(outStream, 0, outStream.Length);
                serverStream.Flush();
                byte[] inStream = new byte[10025];
                serverStream.Read(inStream, 0, (int)clientSocket.ReceiveBufferSize);
                string returnData = System.Text.Encoding.ASCII.GetString(inStream);
                chatBox.AppendText(">> Server: " + returnData);
            }
            catch (Exception ex) 
            {
                MessageBox.Show("Unable to Send Data: " + ex);
            }
        }
    }
}

每次我执行服务器代码时，它都会工作并启动。 但是当我执行客户端时，服务器会抛出错误

指定的参数超出范围

这是完整的错误：

System.ArgumentOutOfRangeException：指定的参数超出了有效值的范围。

参数名称：尺寸

在 System.Net.Sockets.NetworkStream.Read（字节 [] 缓冲区，Int32 偏移量，Int32 大小）
在 TCP_Server_Console.Program.Main(String[] args) 在 C:\Users\user\Documents\Visual Studio 2015\Projects\TCP_Server_Console\TCP_Server_Console\Program.cs:line 50

每次单击客户端表单中的btn_send时，我也会收到相同的错误。

我被困在这里，我不知道问题出在哪里，因为这是我第一次使用 TCP Socket。

任何人都可以帮助我吗？

Answer 1

问题在于您的代码使用了两种不同的大小

byte[] inStream = new byte[10025];
serverStream.Read(inStream, 0, (int)clientSocket.ReceiveBufferSize);

在这。 您为 10025 字节保留了空间，但 RecieveBufferSize 可能是另一个大小，更大或更小，但如果更大，它会出错。

如果您将读取调用调用与字节数组的长度相同，您将不会遇到问题。

Answer 2

            byte[] inStream = new byte[10025];
            byte[] tStream = new byte[(int)clientSocket.ReceiveBufferSize];

            serverStream.Read(tStream, 0, (int)clientSocket.ReceiveBufferSize);

将是确保其读取的字节缓冲区始终是所需的正确大小的快速简单修复。