c# winform socket网络编程，点对点传输文件，socket文件传输，监听端口

http://www.cnblogs.com/vhtt/

服务器用来接收文件，不停的监听端口，有发送文件就马上开始接收文件 
服务端代码： 

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


using System.Net;
using System.Threading;
using System.Net.Sockets;

using System.IO;

namespace TestSocketServerHSTF
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();


            //不显示出dataGridView1的最后一行空白
            dataGridView1.AllowUserToAddRows = false;
        }


        #region 定义变量


        #endregion



        #region 进入窗体即启动服务

        private void Form1_Load(object sender, EventArgs e)
        {
            //开启接收线程
            Thread TempThread = new Thread(new ThreadStart(this.StartReceive));
            TempThread.Start();
        }


        #endregion



        #region 功能函数

        private void StartReceive()
        {
            //创建一个网络端点
            IPEndPoint ipep = new IPEndPoint(IPAddress.Any, int.Parse("2005"));

            //MessageBox.Show(IPAddress.Any);

            //创建一个套接字
            Socket server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

            //绑定套接字到端口
            server.Bind(ipep);

            //开始侦听(并堵塞该线程)
            server.Listen(10);

            //确认连接
            Socket client = server.Accept();

            //获得客户端节点对象
            IPEndPoint clientep = (IPEndPoint)client.RemoteEndPoint;



            //获得[文件名]
            string SendFileName = System.Text.Encoding.Unicode.GetString(TransferFiles.ReceiveVarData(client));
            //MessageBox.Show("文件名" + SendFileName);

            //获得[包的大小]
            string bagSize = System.Text.Encoding.Unicode.GetString(TransferFiles.ReceiveVarData(client));
            //MessageBox.Show("包大小" + bagSize);

            //获得[包的总数量]
            int bagCount = int.Parse(System.Text.Encoding.Unicode.GetString(TransferFiles.ReceiveVarData(client)));
            //MessageBox.Show("包的总数量" + bagCount);

            //获得[最后一个包的大小]
            string bagLast = System.Text.Encoding.Unicode.GetString(TransferFiles.ReceiveVarData(client));
            //MessageBox.Show("最后一个包的大小" + bagLast);

            //创建一个新文件
            FileStream MyFileStream = new FileStream(SendFileName, FileMode.Create, FileAccess.Write);

            //已发送包的个数
            int SendedCount = 0;

            while (true)
            {
                byte[] data = TransferFiles.ReceiveVarData(client);
                if (data.Length == 0)
                {
                    break;
                }
                else
                {
                    SendedCount++;
                    //将接收到的数据包写入到文件流对象
                    MyFileStream.Write(data, 0, data.Length);
                    //显示已发送包的个数
                    //MessageBox.Show("已发送包个数"+SendedCount.ToString());
                }
            }

            //关闭文件流
            MyFileStream.Close();
            //关闭套接字
            client.Close();

            //填加到dgv里
            //文件大小，IP，已发送包的个数，文件名，包的总量，最后一个包的大小
            this.dataGridView1.Rows.Add(bagSize, clientep.Address, SendedCount, SendFileName, bagCount, bagLast);

            //MessageBox.Show("文件接收完毕!");

        }


        #endregion



        #region   拦截Windows消息,关闭窗体时执行
        protected override void WndProc(ref   Message m)
        {
            const int WM_SYSCOMMAND = 0x0112;
            const int SC_CLOSE = 0xF060;
            if (m.Msg == WM_SYSCOMMAND && (int)m.WParam == SC_CLOSE)
            {//捕捉关闭窗体消息
                //   User   clicked   close   button
                //this.WindowState = FormWindowState.Minimized;//把右上角红叉关闭按钮变最小化

                ServiceStop();
            }
            base.WndProc(ref   m);
        }
        #endregion


        #region 停止服务

        //停止服务
        private void ServiceStop()
        {
            try
            {

            }
            catch { }

            try
            {

            }
            catch { }
        }

        #endregion

    }
}

客户端用来发送文件，选择文件后点发送按钮发送文件 
客户端代码： 

////////////////////////////////////////////////////////////////////////////////
//title: 点对点文件传输程序                                           //
////////////////////////////////////////////////////////////////////////////////

//////////////////////////Begin-发送端//////////////////////////////////
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.IO;
using System.Net;
using System.Net.Sockets;
using System.Threading;

namespace 发送端
{
    /// <summary>
    /// Form1 的摘要说明。
    /// </summary>
    public class Form1 : System.Windows.Forms.Form
    {
        private System.Windows.Forms.GroupBox groupBox1;
        private System.Windows.Forms.OpenFileDialog openFileDialog1;
        private System.Windows.Forms.TextBox textBox1;
        private System.Windows.Forms.Button button1;
        private System.Windows.Forms.Label label1;
        private System.Windows.Forms.TextBox textBox2;
        private System.Windows.Forms.Label label2;
        private System.Windows.Forms.TextBox textBox3;
        private System.Windows.Forms.GroupBox groupBox2;
        private System.Windows.Forms.Label label3;
        private System.Windows.Forms.TextBox textBox4;
        private System.Windows.Forms.Label label4;
        private System.Windows.Forms.TextBox textBox5;
        private System.Windows.Forms.GroupBox groupBox3;
        private System.Windows.Forms.GroupBox groupBox4;
        private System.Windows.Forms.Button button2;
        private System.Windows.Forms.Label label5;
        private System.Windows.Forms.TextBox textBox6;
        private System.Windows.Forms.Label label6;
        private System.Windows.Forms.Label label7;
        private System.Windows.Forms.ProgressBar progressBar1;
        private System.Windows.Forms.TextBox textBox7;
        private System.Windows.Forms.Label label8;
        private System.Windows.Forms.Label label9;
        private System.Windows.Forms.TextBox textBox8;
        private System.Windows.Forms.Label label10;
        private System.Windows.Forms.TextBox textBox9;
        private System.Windows.Forms.Label label11;
        private System.Windows.Forms.Label label12;
        private System.Windows.Forms.TextBox textBox10;
        /// <summary>
        /// 必需的设计器变量。
        /// </summary>
        private System.ComponentModel.Container components = null;

        public Form1()
        {
            //
            // Windows 窗体设计器支持所必需的
            //
            InitializeComponent();

            //
            // TODO: 在 InitializeComponent 调用后添加任何构造函数代码
            //
        }

        /// <summary>
        /// 清理所有正在使用的资源。
        /// </summary>
        protected override void Dispose( bool disposing )
        {
            if( disposing )
            {
                if (components != null)
                {
                    components.Dispose();
                }
            }
            base.Dispose( disposing );
        }

        #region Windows 窗体设计器生成的代码
        /// <summary>
        /// 设计器支持所需的方法 - 不要使用代码编辑器修改
        /// 此方法的内容。
        /// </summary>
        private void InitializeComponent()
        {
            this.groupBox1 = new System.Windows.Forms.GroupBox();
            this.textBox2 = new System.Windows.Forms.TextBox();
            this.textBox3 = new System.Windows.Forms.TextBox();
            this.label2 = new System.Windows.Forms.Label();
            this.label1 = new System.Windows.Forms.Label();
            this.button1 = new System.Windows.Forms.Button();
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.label6 = new System.Windows.Forms.Label();
            this.openFileDialog1 = new System.Windows.Forms.OpenFileDialog();
            this.groupBox2 = new System.Windows.Forms.GroupBox();
            this.textBox6 = new System.Windows.Forms.TextBox();
            this.textBox5 = new System.Windows.Forms.TextBox();
            this.label4 = new System.Windows.Forms.Label();
            this.textBox4 = new System.Windows.Forms.TextBox();
            this.label3 = new System.Windows.Forms.Label();
            this.label5 = new System.Windows.Forms.Label();
            this.label9 = new System.Windows.Forms.Label();
            this.groupBox3 = new System.Windows.Forms.GroupBox();
            this.textBox8 = new System.Windows.Forms.TextBox();
            this.textBox9 = new System.Windows.Forms.TextBox();
            this.textBox7 = new System.Windows.Forms.TextBox();
            this.progressBar1 = new System.Windows.Forms.ProgressBar();
            this.label7 = new System.Windows.Forms.Label();
            this.label8 = new System.Windows.Forms.Label();
            this.label10 = new System.Windows.Forms.Label();
            this.label11 = new System.Windows.Forms.Label();
            this.label12 = new System.Windows.Forms.Label();
            this.textBox10 = new System.Windows.Forms.TextBox();
            this.groupBox4 = new System.Windows.Forms.GroupBox();
            this.button2 = new System.Windows.Forms.Button();
            this.groupBox1.SuspendLayout();
            this.groupBox2.SuspendLayout();
            this.groupBox3.SuspendLayout();
            this.groupBox4.SuspendLayout();
            this.SuspendLayout();
            //
            // groupBox1
            //
            this.groupBox1.Controls.Add(this.textBox2);
            this.groupBox1.Controls.Add(this.textBox3);
            this.groupBox1.Controls.Add(this.label2);
            this.groupBox1.Controls.Add(this.label1);
            this.groupBox1.Controls.Add(this.button1);
            this.groupBox1.Controls.Add(this.textBox1);
            this.groupBox1.Controls.Add(this.label6);
            this.groupBox1.Location = new System.Drawing.Point(0, 0);
            this.groupBox1.Name = "groupBox1";
            this.groupBox1.Size = new System.Drawing.Size(416, 96);
            this.groupBox1.TabIndex = 0;
            this.groupBox1.TabStop = false;
            this.groupBox1.Text = "文件信息";
            //
            // textBox2
            //
            this.textBox2.Location = new System.Drawing.Point(80, 40);
            this.textBox2.Name = "textBox2";
            this.textBox2.ReadOnly = true;
            this.textBox2.Size = new System.Drawing.Size(232, 21);
            this.textBox2.TabIndex = 3;
            //
            // textBox3
            //
            this.textBox3.Location = new System.Drawing.Point(80, 64);
            this.textBox3.Name = "textBox3";
            this.textBox3.ReadOnly = true;
            this.textBox3.Size = new System.Drawing.Size(136, 21);
            this.textBox3.TabIndex = 3;
            //
            // label2
            //
            this.label2.Location = new System.Drawing.Point(8, 72);
            this.label2.Name = "label2";
            this.label2.Size = new System.Drawing.Size(100, 16);
            this.label2.TabIndex = 4;
            this.label2.Text = "文件大小：";
            //
            // label1
            //
            this.label1.Location = new System.Drawing.Point(16, 48);
            this.label1.Name = "label1";
            this.label1.Size = new System.Drawing.Size(96, 16);
            this.label1.TabIndex = 2;
            this.label1.Text = "文件名：";
            //
            // button1
            //
            this.button1.Location = new System.Drawing.Point(320, 16);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(88, 23);
            this.button1.TabIndex = 1;
            this.button1.Text = "浏览";
            this.button1.Click += new System.EventHandler(this.button1_Click);
            //
            // textBox1
            //
            this.textBox1.Location = new System.Drawing.Point(8, 16);
            this.textBox1.Name = "textBox1";
            this.textBox1.ReadOnly = true;
            this.textBox1.Size = new System.Drawing.Size(304, 21);
            this.textBox1.TabIndex = 0;
            //
            // label6
            //
            this.label6.Location = new System.Drawing.Point(224, 72);
            this.label6.Name = "label6";
            this.label6.Size = new System.Drawing.Size(96, 16);
            this.label6.TabIndex = 2;
            this.label6.Text = "（单位：字节）";
            //
            // openFileDialog1
            //
            this.openFileDialog1.Filter = "所有文件|*.*";
            //
            // groupBox2
            //
            this.groupBox2.Controls.Add(this.textBox6);
            this.groupBox2.Controls.Add(this.textBox5);
            this.groupBox2.Controls.Add(this.label4);
            this.groupBox2.Controls.Add(this.textBox4);
            this.groupBox2.Controls.Add(this.label3);
            this.groupBox2.Controls.Add(this.label5);
            this.groupBox2.Controls.Add(this.label9);
            this.groupBox2.Location = new System.Drawing.Point(0, 96);
            this.groupBox2.Name = "groupBox2";
            this.groupBox2.Size = new System.Drawing.Size(416, 72);
            this.groupBox2.TabIndex = 1;
            this.groupBox2.TabStop = false;
            this.groupBox2.Text = "系统设置";
            //
            // textBox6
            //
            this.textBox6.Location = new System.Drawing.Point(96, 40);
            this.textBox6.Name = "textBox6";
            this.textBox6.Size = new System.Drawing.Size(72, 21);
            this.textBox6.TabIndex = 3;
            this.textBox6.Text = "50000";
            //
            // textBox5
            //
            this.textBox5.Location = new System.Drawing.Point(320, 16);
            this.textBox5.Name = "textBox5";
            this.textBox5.Size = new System.Drawing.Size(80, 21);
            this.textBox5.TabIndex = 3;
            this.textBox5.Text = "2005";
            //
            // label4
            //
            this.label4.Location = new System.Drawing.Point(256, 24);
            this.label4.Name = "label4";
            this.label4.Size = new System.Drawing.Size(100, 16);
            this.label4.TabIndex = 2;
            this.label4.Text = "传输端口：";
            //
            // textBox4
            //
            this.textBox4.Location = new System.Drawing.Point(96, 16);
            this.textBox4.Name = "textBox4";
            this.textBox4.ReadOnly = true;
            this.textBox4.Size = new System.Drawing.Size(144, 21);
            this.textBox4.TabIndex = 1;
            //
            // label3
            //
            this.label3.Location = new System.Drawing.Point(16, 24);
            this.label3.Name = "label3";
            this.label3.Size = new System.Drawing.Size(100, 16);
            this.label3.TabIndex = 0;
            this.label3.Text = "本机IP地址：";
            //
            // label5
            //
            this.label5.Location = new System.Drawing.Point(24, 48);
            this.label5.Name = "label5";
            this.label5.Size = new System.Drawing.Size(88, 16);
            this.label5.TabIndex = 2;
            this.label5.Text = "包的大小：";
            //
            // label9
            //
            this.label9.Location = new System.Drawing.Point(176, 48);
            this.label9.Name = "label9";
            this.label9.Size = new System.Drawing.Size(224, 16);
            this.label9.TabIndex = 2;
            this.label9.Text = "（范围：10000 - 60000 单位：字节）";
            //
            // groupBox3
            //
            this.groupBox3.Controls.Add(this.textBox8);
            this.groupBox3.Controls.Add(this.textBox9);
            this.groupBox3.Controls.Add(this.textBox7);
            this.groupBox3.Controls.Add(this.progressBar1);
            this.groupBox3.Controls.Add(this.label7);
            this.groupBox3.Controls.Add(this.label8);
            this.groupBox3.Controls.Add(this.label10);
            this.groupBox3.Controls.Add(this.label11);
            this.groupBox3.Controls.Add(this.label12);
            this.groupBox3.Controls.Add(this.textBox10);
            this.groupBox3.Location = new System.Drawing.Point(0, 168);
            this.groupBox3.Name = "groupBox3";
            this.groupBox3.Size = new System.Drawing.Size(416, 168);
            this.groupBox3.TabIndex = 2;
            this.groupBox3.TabStop = false;
            this.groupBox3.Text = "状态信息";
            //
            // textBox8
            //
            this.textBox8.Location = new System.Drawing.Point(120, 40);
            this.textBox8.Name = "textBox8";
            this.textBox8.ReadOnly = true;
            this.textBox8.Size = new System.Drawing.Size(160, 21);
            this.textBox8.TabIndex = 1;
            //
            // textBox9
            //
            this.textBox9.Location = new System.Drawing.Point(120, 64);
            this.textBox9.Name = "textBox9";
            this.textBox9.ReadOnly = true;
            this.textBox9.Size = new System.Drawing.Size(80, 21);
            this.textBox9.TabIndex = 1;
            //
            // textBox7
            //
            this.textBox7.Location = new System.Drawing.Point(120, 16);
            this.textBox7.Name = "textBox7";
            this.textBox7.ReadOnly = true;
            this.textBox7.Size = new System.Drawing.Size(160, 21);
            this.textBox7.TabIndex = 1;
            //
            // progressBar1
            //
            this.progressBar1.Location = new System.Drawing.Point(8, 136);
            this.progressBar1.Name = "progressBar1";
            this.progressBar1.Size = new System.Drawing.Size(400, 23);
            this.progressBar1.Step = 1;
            this.progressBar1.TabIndex = 3;
            //
            // label7
            //
            this.label7.Location = new System.Drawing.Point(32, 24);
            this.label7.Name = "label7";
            this.label7.Size = new System.Drawing.Size(96, 16);
            this.label7.TabIndex = 2;
            this.label7.Text = "接收端IP地址：";
            //
            // label8
            //
            this.label8.Location = new System.Drawing.Point(40, 48);
            this.label8.Name = "label8";
            this.label8.Size = new System.Drawing.Size(80, 16);
            this.label8.TabIndex = 2;
            this.label8.Text = "包的总数量：";
            //
            // label10
            //
            this.label10.Location = new System.Drawing.Point(8, 72);
            this.label10.Name = "label10";
            this.label10.Size = new System.Drawing.Size(120, 16);
            this.label10.TabIndex = 2;
            this.label10.Text = "最后一个包的大小：";
            //
            // label11
            //
            this.label11.Location = new System.Drawing.Point(200, 72);
            this.label11.Name = "label11";
            this.label11.Size = new System.Drawing.Size(96, 16);
            this.label11.TabIndex = 2;
            this.label11.Text = "（单位：字节）";
            //
            // label12
            //
            this.label12.Location = new System.Drawing.Point(16, 96);
            this.label12.Name = "label12";
            this.label12.Size = new System.Drawing.Size(104, 16);
            this.label12.TabIndex = 2;
            this.label12.Text = "已发送包的数量：";
            //
            // textBox10
            //
            this.textBox10.Location = new System.Drawing.Point(120, 88);
            this.textBox10.Name = "textBox10";
            this.textBox10.ReadOnly = true;
            this.textBox10.Size = new System.Drawing.Size(80, 21);
            this.textBox10.TabIndex = 1;
            //
            // groupBox4
            //
            this.groupBox4.Controls.Add(this.button2);
            this.groupBox4.Location = new System.Drawing.Point(0, 336);
            this.groupBox4.Name = "groupBox4";
            this.groupBox4.Size = new System.Drawing.Size(416, 48);
            this.groupBox4.TabIndex = 3;
            this.groupBox4.TabStop = false;
            this.groupBox4.Text = "系统控制";
            //
            // button2
            //
            this.button2.Location = new System.Drawing.Point(16, 16);
            this.button2.Name = "button2";
            this.button2.Size = new System.Drawing.Size(75, 23);
            this.button2.TabIndex = 0;
            this.button2.Text = "开始发送";
            this.button2.Click += new System.EventHandler(this.button2_Click);
            //
            // Form1
            //
            this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
            this.ClientSize = new System.Drawing.Size(416, 389);
            this.Controls.Add(this.groupBox4);
            this.Controls.Add(this.groupBox3);
            this.Controls.Add(this.groupBox2);
            this.Controls.Add(this.groupBox1);
            this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle;
            this.MaximizeBox = false;
            this.Name = "Form1";
            this.Text = "点对点文件传输软体发送端";
            this.Load += new System.EventHandler(this.EzoneSend_Load);
            this.groupBox1.ResumeLayout(false);
            this.groupBox1.PerformLayout();
            this.groupBox2.ResumeLayout(false);
            this.groupBox2.PerformLayout();
            this.groupBox3.ResumeLayout(false);
            this.groupBox3.PerformLayout();
            this.groupBox4.ResumeLayout(false);
            this.ResumeLayout(false);

        }
        #endregion

        /// <summary>
        /// 应用程序的主入口点。
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.Run(new Form1());
        }

        private void button1_Click(object sender, System.EventArgs e)
        {
            //选择要进行传输的文件
            if(this.openFileDialog1.ShowDialog()==DialogResult.OK)
            {
                FileInfo EzoneFile=new FileInfo(this.openFileDialog1.FileName);
                this.textBox1.Text=EzoneFile.FullName;
                this.textBox2.Text=EzoneFile.Name;
                this.textBox3.Text=EzoneFile.Length.ToString();

            }
        }


        private void StartSend()
        {
            //创建一个文件对象
            FileInfo EzoneFile=new FileInfo(this.textBox1.Text);
            //打开文件流
            FileStream EzoneStream=EzoneFile.OpenRead();
            //包的大小
            int PacketSize=int.Parse(this.textBox6.Text);
            //包的数量
            int PacketCount=(int)(EzoneStream.Length/((long)PacketSize));
            this.textBox8.Text=PacketCount.ToString();
            this.progressBar1.Maximum=PacketCount;
            //最后一个包的大小
            int LastDataPacket=(int)(EzoneStream.Length-((long)(PacketSize*PacketCount)));
            this.textBox9.Text=LastDataPacket.ToString();

            ////创建一个网络端点
            //IPEndPoint ipep = new IPEndPoint(IPAddress.Parse("192.168.1.136"), int.Parse(this.textBox5.Text));

            ////MessageBox.Show(IPAddress.Any);

            ////创建一个套接字
            //Socket client = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

            //MessageBox.Show(server.ToString());



            //指向远程服务端节点
            IPEndPoint ipep = new IPEndPoint(IPAddress.Parse("192.168.1.136"), int.Parse(this.textBox5.Text));
            //创建套接字
            Socket client = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            //连接到发送端
            client.Connect(ipep);





            ////绑定套接字到端口
            //client.Bind(ipep);

            //MessageBox.Show(ipep.ToString());

            ////开始侦听(并堵塞该线程)
            //server.Listen(10);
            //确认连接
            //Socket client = server.Accept();

            //MessageBox.Show(client.ToString());







            //获得客户端节点对象
            IPEndPoint clientep=(IPEndPoint)client.RemoteEndPoint;
            //获得客户端的IP地址
            //this.textBox7.Text=clientep.Address.ToString();
            //发送[文件名]到客户端
            CommonModule.EzoneModule.SendVarData(client,System.Text.Encoding.Unicode.GetBytes(EzoneFile.Name));
            //发送[包的大小]到客户端
            CommonModule.EzoneModule.SendVarData(client,System.Text.Encoding.Unicode.GetBytes(PacketSize.ToString()));
            //发送[包的总数量]到客户端
            CommonModule.EzoneModule.SendVarData(client,System.Text.Encoding.Unicode.GetBytes(PacketCount.ToString()));
            //发送[最后一个包的大小]到客户端
            CommonModule.EzoneModule.SendVarData(client,System.Text.Encoding.Unicode.GetBytes(LastDataPacket.ToString()));

            //数据包
            byte[] data=new byte[PacketSize];
            //开始循环发送数据包
            for(int i=0;i<PacketCount;i++)
            {
                //从文件流读取数据并填充数据包
                EzoneStream.Read(data,0,data.Length);
                //发送数据包
                CommonModule.EzoneModule.SendVarData(client,data);
                //显示发送数据包的个数
                this.textBox10.Text=((int)(i+1)).ToString();
                //进度条值的显示
                this.progressBar1.PerformStep();
            }

            //如果还有多余的数据包,则应该发送完毕!
            if(LastDataPacket!=0)
            {
                data=new byte[LastDataPacket];
                EzoneStream.Read(data,0,data.Length);
                CommonModule.EzoneModule.SendVarData(client,data);
                this.progressBar1.Value=this.progressBar1.Maximum;
            }

            //关闭套接字
            client.Close();
            //server.Close();
            //关闭文件流
            EzoneStream.Close();
            this.button2.Enabled=true;
            MessageBox.Show("文件传输完毕!");
        }


        private void button2_Click(object sender, System.EventArgs e)
        {
            //开启文件传输子线程
            Thread TempThread=new Thread(new ThreadStart(this.StartSend));
            TempThread.Start();
            this.button2.Enabled=false;
        }

        private void EzoneSend_Load(object sender, System.EventArgs e)
        {
            //获得本机的IP地址
            this.textBox4.Text=Dns.GetHostByName(Dns.GetHostName()).AddressList[0].ToString();
        }
    }
}

公共类，服务端客户端都需要用到 

////////////////////////////Begin-公共模块//////////////////////////////////////


using System;
using System.Collections.Generic;
using System.Text;

using System.Net;
using System.Net.Sockets;
using System.Windows.Forms;

namespace TestSocketServerHSTF
{
    class TransferFiles
    {
        public TransferFiles()
        {
            //
            // TODO: 在此处添加构造函数逻辑
            //
        }



        public static int SendData(Socket s, byte[] data)
        {
            int total = 0;
            int size = data.Length;
            int dataleft = size;
            int sent;

            while (total < size)
            {
                sent = s.Send(data, total, dataleft, SocketFlags.None);
                total += sent;
                dataleft -= sent;
            }

            return total;
        }

        public static byte[] ReceiveData(Socket s, int size)
        {
            int total = 0;
            int dataleft = size;
            byte[] data = new byte[size];
            int recv;
            while (total < size)
            {
                recv = s.Receive(data, total, dataleft, SocketFlags.None);
                if (recv == 0)
                {
                    data = null;
                    break;
                }

                total += recv;
                dataleft -= recv;
            }
            return data;
        }

        public static int SendVarData(Socket s, byte[] data)
        {
            int total = 0;
            int size = data.Length;
            int dataleft = size;
            int sent;
            byte[] datasize = new byte[4];
            datasize = BitConverter.GetBytes(size);
            sent = s.Send(datasize);

            while (total < size)
            {
                sent = s.Send(data, total, dataleft, SocketFlags.None);
                total += sent;
                dataleft -= sent;
            }

            return total;
        }

        public static byte[] ReceiveVarData(Socket s)
        {
            int total = 0;
            int recv;
            byte[] datasize = new byte[4];
            recv = s.Receive(datasize, 0, 4, SocketFlags.None);
            int size = BitConverter.ToInt32(datasize, 0);
            int dataleft = size;
            byte[] data = new byte[size];
            while (total < size)
            {
                recv = s.Receive(data, total, dataleft, SocketFlags.None);
                if (recv == 0)
                {
                    data = null;
                    break;
                }
                total += recv;
                dataleft -= recv;
            }
            return data;
        }
    }
}




/////////////////////////////End-公共模块///////////////////////////////////////