TCP编程-端口扫描器与网游客户端

一、编写端口扫描器程序

打开Visual Studio,选择Windows 窗体应用

（一）单线程实现扫描

窗体设计

代码实现

using System;
using System.Windows.Forms;
using System.Net;
using System.Net.Sockets;
namespace Scan1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        private int port;
        private string Address;
        private bool[] done = new bool[65536];
        private int start;
        private int end;
        private bool OK;
        
        private void button1_Click(object sender, EventArgs e)
        {
            label4.Text = textBox2.Text;
            label6.Text = textBox3.Text;
            progressBar1.Minimum = Int32.Parse(textBox2.Text);
            progressBar1.Maximum = Int32.Parse(textBox3.Text);
            listBox1.Items.Clear();
            listBox1.Items.Add("端口扫描器v1.0.");
            listBox1.Items.Add("");
            Scan1();
        }
        private void Scan1()
        {
            start = Int32.Parse(textBox2.Text);
            end = Int32.Parse(textBox3.Text);
            if ((start >= 0 && start <= 65536) && (end >= 0 && end <= 65536) && (start <= end))
            {
                listBox1.Items.Add("开始扫描：这个过程可能需要等待几分钟！");
                Address = textBox1.Text;
                for (int i = start; i <= end; i++)
                {
                    port = i;
                    Scan1();
                    progressBar1.Value = i;
                    label5.Text = i.ToString();
                }
                while (!OK)
                {
                    OK = true;
                    Scan1();
                    for (int i = start; i <= end; i++)
                    {
                        if (!done[i])
                        {
                            OK = false;
                            break;
                        }
                    }

                }
                listBox1.Items.Add("扫描结束！");
            }
            else
            {
                MessageBox.Show("输入错误！端口范围为[0,65536]");
            }
        }
        private void Scan()
        {
            int portnow = port;
            done[portnow] = true;
            TcpClient objTCP = null;
            try
            {
                objTCP = new TcpClient(Address, portnow);
                listBox1.Items.Add("端口" + portnow.ToString() + "开放");
            }
            catch 
            {
                
            }
        }
    }
}

结果显示

（二）多线程实现扫描

代码实现：

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

namespace Scan2
{
    public partial class Form1 : Form
    {
        private int startPort;
        private int endPort;
        private string IP;
        private int port;
        private bool[] done = new bool[65536];
        public Form1()
        {
            InitializeComponent();
            listBox1.Items.Add("欢迎使用端口扫描器v1.0!");
            this.Text = "端口扫描器v1.0";
        }

        private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
        {

        }
        private void label1_Click(object sender, EventArgs e)
        {

        }
        private void start_Port(object sender, EventArgs e)
        {
            label4.Text = textBox2.Text;
            try
            {
                //string转int，如果字符串为空，则抛出ArgumentNullException异常；
                //如果字符串内容不是数字，则抛出FormatException异常；
                startPort = int.Parse(textBox2.Text);
            }
            catch
            {
            }
        }

        //获取结束端口
        private void end_Port(object sender, EventArgs e)
        {
            label6.Text = textBox3.Text;
            try
            {
                endPort = int.Parse(textBox3.Text);
            }
            catch
            {
            }
        }

        //获取IP地址
        private void get_IP(object sender, EventArgs e)
        {
            IP = textBox1.Text;
        }

        //IP检验
        private bool judge_IP()
        {
            int n = IP.Length;
            int[] x = new int[5] { 0, 0, 0, 0, 0 };
            int sum = 0;
            int j = 0;
            for (int i = 0; i < n; i++)
            {
                if (IP[i] == '.')
                {
                    x[j] = sum;
                    sum = 0;
                    j++;
                    continue;
                }
                if (j == 4 || (IP[i] == '.' && IP[i + 1] == '.'))
                {
                    return false;
                }
                sum = sum * 10 + (IP[i] - '0');
            }
            if (j == 3)
            {
                x[j] = sum;
                for (int i = 0; i < 4; i++)
                {
                    if (x[i] < 0 || x[i] > 255)
                    {
                        return false;
                    }
                }
                return true;
            }
            return false;
        }

        private void Scan()
        {
            int portnow = port;
            //记录该端口已访问
            done[portnow] = true;
            try
            {
                TcpClient tcp = new TcpClient(IP, portnow);
                //listBox1.Items.Add("端口 " + portnow.ToString() + " 开放！");
                this.Invoke((EventHandler)delegate
                {
                    listBox1.Items.Add("端口 " + portnow.ToString() + " 开放！");
                });
            }
            catch
            {
            }
        }

        private void port_Scan()
        {
            //检查端口合法性
            if ((startPort >= 0 && startPort <= 65535) && (endPort >= 0 && endPort <= 65535) && (startPort <= endPort))
            {
                if (IP != "" && judge_IP())
                {
                    //listBox1.Items.Clear();
                    this.Invoke((EventHandler)delegate
                    {
                        listBox1.Items.Clear();
                        button1.Enabled = false;
                        listBox1.Items.Add("开始扫描……(该过程可能会等待一定时间！)");
                    });
                    //listBox1.Items.Add("开始扫描……(该过程可能会等待一定时间！)");
                    for (int i = startPort; i <= endPort; i++)
                    {
                        port = i;
                        //创建该端口的扫描线程
                        ThreadStart childScan = new ThreadStart(Scan);
                        Thread scanThread = new Thread(childScan);
                        scanThread.Start();
                        //使线程暂停100ms
                        System.Threading.Thread.Sleep(100);
                        //progressBar1.Value = i;
                        this.Invoke((EventHandler)delegate
                        {
                            progressBar1.Value = i;
                            label5.Text = i.ToString();
                        });
                    }
                    bool flag = true;
                    while (flag)
                    {
                        int i;
                        for (i = startPort; i <= endPort; i++)
                        {
                            if (!done[i])
                            {
                                break;
                            }
                        }
                        if (i == endPort + 1)
                        {
                            flag = false;
                        }
                        //线程暂停2000ms
                        System.Threading.Thread.Sleep(2000);
                    }
                    this.Invoke((EventHandler)delegate
                    {
                        listBox1.Items.Add("扫描结束！！！");
                        button1.Enabled = true;
                    });
                    //listBox1.Items.Add("扫描结束！！！");
                }
                else
                {
                    MessageBox.Show("IP地址不合法！", "Error", MessageBoxButtons.OKCancel, MessageBoxIcon.Error);
                }
            }
            else
            {
                //错误消息反馈
                MessageBox.Show("端口不合法！", "Error", MessageBoxButtons.OKCancel, MessageBoxIcon.Error);
            }
        }

        //开始扫描
        private void button_Click(object sender, EventArgs e)
        {
            //port_Scan();
            //创建线程，并创建 ThreadStart 委托对象
            ThreadStart childScan = new ThreadStart(port_Scan);
            Thread childThread = new Thread(childScan);
            childThread.Start();
            //显示端口扫描范围
            progressBar1.Minimum = startPort;
            progressBar1.Maximum = endPort;
            //main_Thread();
            //显示初始化端口信息
            listBox1.Items.Clear();
            listBox1.Items.Add("欢迎使用端口扫描器 v1.0！！！");
        }


        //用单一进程测试端口扫描
        private void main_Thread()
        {
            listBox1.Items.Add("开始扫描……(该过程可能会等待一定时间！)");
            for (int i = startPort; i <= endPort; i++)
            {
                progressBar1.Value = i;
                label5.Text = i.ToString();
                try
                {
                    TcpClient tcp = new TcpClient(IP, i);
                    listBox1.Items.Add("端口 " + i.ToString() + " 开放！");
                }
                catch
                {
                }
            }
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void progressBar1_Click(object sender, EventArgs e)
        {

        }
    }
}

结果显示：

二、编写网游客户端