Question

我正在用c＃编写一个telnet客户端和服务器。问题是当我在客户端中输入命令时。我的服务器给出错误： “系统无法找到指定的文件”

我的服务器位于控制台应用程序中，我的客户端处于winform状态。非常感谢你。

以下是代码： 服务器

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

namespace TelnetServerVictim
{
    class Program
    {
        static void Main(string[] args)
        {
            IPAddress HOST = IPAddress.Parse("127.0.0.1");
            IPEndPoint serverEP = new IPEndPoint(HOST, 443);
            Socket sck = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            sck.Bind(serverEP);
            sck.Listen(443);

            try
            {
                Console.WriteLine("Listening for clients...");
                Socket msg = sck.Accept();

                while (true)
                {
                    // Send a welcome greet
                    byte[] buffer = Encoding.Default.GetBytes("Welcome to the server of Kobernicus!!");
                    msg.Send(buffer, 0, buffer.Length, 0);
                    buffer = new byte[255];

                    // Read the sended command
                    int rec = msg.Receive(buffer, 0, buffer.Length, 0);
                    byte[] bufferReaction = Encoding.Default.GetBytes(rec.ToString());

                    // Run the command
                    Process prcsCMD = new Process();
                    prcsCMD.StartInfo.FileName = bufferReaction.ToString();
                    prcsCMD.StartInfo.UseShellExecute = false;
                    prcsCMD.StartInfo.Arguments = string.Empty;
                    prcsCMD.StartInfo.RedirectStandardOutput = true;
                    prcsCMD.Start();

                    string output = prcsCMD.StandardOutput.ReadToEnd();
                    byte[] cmdOutput = Encoding.Default.GetBytes(output);
                    msg.Send(cmdOutput,0,cmdOutput.Length,0);
                    cmdOutput = new byte[255];
                }
                sck.Close();
                msg.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
        }
    }
}

客户端：

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

namespace TelnetClientME
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        Socket sck;
        private void btnConnect_Click(object sender, EventArgs e)
        {
            sck = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            IPEndPoint endPoint = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 443);
            try
            {
                sck.Connect(endPoint);
                MessageBox.Show("You are connected to the server!");
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void btnSendMSG_Click(object sender, EventArgs e)
        {
            byte[] buffer = Encoding.Default.GetBytes(txtCMD.Text);
            sck.Send(buffer, 0, buffer.Length, 0);
            buffer = new byte[255];
            int rec = sck.Receive(buffer, 0, buffer.Length, 0);

            txtOutputCMD.Text = rec.ToString();
        }

        private void btnClear_Click(object sender, EventArgs e)
        {
            txtOutputCMD.Clear();
        }

        private void btnExit_Click(object sender, EventArgs e)
        {
            sck.Close();
            Application.Exit();
        }
    }
}

非常感谢你。 txtOutputCMD =一个richTextBox，命令的输出应该是。 txtCMD =您可以在其中键入命令的文本框。

Answer 1

byte [] bufferReaction = Encoding.Default.GetBytes（rec.ToString（））;

只是将读取的字节数转换为字符串，然后再转换为字节数组

您不需要它（这是错误的），因为从客户端发送的字节已经在buffer。

您可能想要使用

var fileName = Encoding.Default.GetString(buffer,0,rec);

PS：不要忘记TCP是面向流的协议，从客户端发送100个字节并不意味着你将从服务器读取100个字节。例如，它可以以两个50字节的块来到达。

C＃Telnet服务器客户端

1 个答案: