第二章-主机扫描

namespace Tcp常规扫描程序
{

    public partial class Form1 : Form
    {
        public int connState=0;
        public int portSum = 0;
        string 主机str;
        int 开始端口 { get { return int.Parse(tex开始端口.Text); } }
        int 结束端口 { get { return int.Parse(tex结束端口.Text); } }
        int 线程数 { get { return int.Parse(tex线程数.Text); } }
        IPAddress ip地址;
        public Form1()
        {
            InitializeComponent();
            Control.CheckForIllegalCrossThreadCalls = false;
        }

        private void 开始bt_Click(object sender, EventArgs e)
        {
            connState = 0;
            portSum = 0;
            主机str = textBox1.Text;

            try
            {
                  ip地址 = IPAddress.Parse(主机str);
                textBox1.Text = ip地址.ToString();
            }
            catch(Exception a)
            {
                textBox1.Focus();
                MessageBox.Show("请输入正确的主句地址,改地址dns无法解析", "系统提示");
                return;
            }

            ThreadPool.SetMaxThreads(线程数, 线程数);//设置最大线程数
            for (int _线程数 = 开始端口; _线程数 <= 结束端口; _线程数++)
            {
                ThreadPool.QueueUserWorkItem(new WaitCallback(正常扫描), _线程数);
            }
        }
 
        public void 正常扫描(object state)
        {
            Int32 port = (Int32)state;
            string tMsg = "";
            string 获取数据 = "";
            connState++;

            try
            {
                TcpClient tcp = new TcpClient();
                tcp.Connect(ip地址, port);
                portSum++;
                tMsg = port.ToString() + "端口开放";
                listBox1.Items.Add(tMsg);

                Stream sm = tcp.GetStream();
                sm.Write(Encoding.Default.GetBytes(tMsg.ToCharArray()), 0, tMsg.Length);
                StreamReader sr = new StreamReader(tcp.GetStream(), Encoding.Default);
                try
                {
                    获取数据 = sr.ReadLine();
                    //这行失败,无法读取协议消息.将自动跳转到catch语句
                    if (获取数据.Length != 0)
                    {
                        tMsg = port.ToString() + "端口数据:" + 获取数据.ToString();
                        listBox1.Items.Add("接受到数据:" + tMsg);
                    }
                }
                catch (Exception a) { }
                finally
                {
                    sr.Close();
                    sm.Close();
                    tcp.Close();
                    Thread.Sleep(0);//制定标识应挂起改线程以使其他等待线程能够执行
                }
            }
            catch (Exception a) { }
            finally
            {
                Thread.Sleep(0);
                //asyncOpsAreDone.Close();
            }
        }
    }
}