简单Socket示例

namespace SocketTest
{
    partial class Server
    {
        /// <summary>
        /// 必需的设计器变量。
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// 清理所有正在使用的资源。
        /// </summary>
        /// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (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.btnOpen = new System.Windows.Forms.Button();
            this.textBox_port = new System.Windows.Forms.TextBox();
            this.label1 = new System.Windows.Forms.Label();
            this.textBox_send = new System.Windows.Forms.TextBox();
            this.button_Send = new System.Windows.Forms.Button();
            this.label2 = new System.Windows.Forms.Label();
            this.label3 = new System.Windows.Forms.Label();
            this.listView_userlist = new System.Windows.Forms.ListView();
            this.richTextBox_record = new System.Windows.Forms.RichTextBox();
            this.SuspendLayout();
            // 
            // btnOpen
            // 
            this.btnOpen.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
            this.btnOpen.Location = new System.Drawing.Point(171, 285);
            this.btnOpen.Name = "btnOpen";
            this.btnOpen.Size = new System.Drawing.Size(75, 20);
            this.btnOpen.TabIndex = 1;
            this.btnOpen.Text = "启动服务";
            this.btnOpen.UseVisualStyleBackColor = true;
            this.btnOpen.Click += new System.EventHandler(this.btnOpen_Click);
            // 
            // textBox_port
            // 
            this.textBox_port.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
            this.textBox_port.Location = new System.Drawing.Point(85, 285);
            this.textBox_port.Name = "textBox_port";
            this.textBox_port.Size = new System.Drawing.Size(60, 20);
            this.textBox_port.TabIndex = 2;
            this.textBox_port.Text = "2001";
            // 
            // label1
            // 
            this.label1.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
            this.label1.AutoSize = true;
            this.label1.Location = new System.Drawing.Point(12, 288);
            this.label1.Name = "label1";
            this.label1.Size = new System.Drawing.Size(67, 13);
            this.label1.TabIndex = 3;
            this.label1.Text = "监听端口：";
            // 
            // textBox_send
            // 
            this.textBox_send.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)
                        | System.Windows.Forms.AnchorStyles.Right)));
            this.textBox_send.Location = new System.Drawing.Point(128, 218);
            this.textBox_send.Multiline = true;
            this.textBox_send.Name = "textBox_send";
            this.textBox_send.ScrollBars = System.Windows.Forms.ScrollBars.Vertical;
            this.textBox_send.Size = new System.Drawing.Size(358, 45);
            this.textBox_send.TabIndex = 4;
            this.textBox_send.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.textBox2_KeyPress);
            // 
            // button_Send
            // 
            this.button_Send.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right)));
            this.button_Send.Enabled = false;
            this.button_Send.Location = new System.Drawing.Point(492, 217);
            this.button_Send.Name = "button_Send";
            this.button_Send.Size = new System.Drawing.Size(45, 46);
            this.button_Send.TabIndex = 5;
            this.button_Send.Text = "发送信息";
            this.button_Send.UseVisualStyleBackColor = true;
            this.button_Send.Click += new System.EventHandler(this.button_Send_Click);
            // 
            // label2
            // 
            this.label2.AutoSize = true;
            this.label2.Location = new System.Drawing.Point(12, 9);
            this.label2.Name = "label2";
            this.label2.Size = new System.Drawing.Size(55, 13);
            this.label2.TabIndex = 7;
            this.label2.Text = "用户列表";
            // 
            // label3
            // 
            this.label3.AutoSize = true;
            this.label3.Location = new System.Drawing.Point(125, 9);
            this.label3.Name = "label3";
            this.label3.Size = new System.Drawing.Size(31, 13);
            this.label3.TabIndex = 8;
            this.label3.Text = "消息";
            // 
            // listView_userlist
            // 
            this.listView_userlist.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)
                        | System.Windows.Forms.AnchorStyles.Left)));
            this.listView_userlist.Location = new System.Drawing.Point(15, 25);
            this.listView_userlist.Name = "listView_userlist";
            this.listView_userlist.Size = new System.Drawing.Size(107, 238);
            this.listView_userlist.TabIndex = 9;
            this.listView_userlist.UseCompatibleStateImageBehavior = false;
            this.listView_userlist.View = System.Windows.Forms.View.List;
            this.listView_userlist.SelectedIndexChanged += new System.EventHandler(this.listView_userlist_SelectedIndexChanged);
            // 
            // richTextBox_record
            // 
            this.richTextBox_record.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)
                        | System.Windows.Forms.AnchorStyles.Left)
                        | System.Windows.Forms.AnchorStyles.Right)));
            this.richTextBox_record.BackColor = System.Drawing.SystemColors.Window;
            this.richTextBox_record.HideSelection = false;
            this.richTextBox_record.Location = new System.Drawing.Point(128, 26);
            this.richTextBox_record.Name = "richTextBox_record";
            this.richTextBox_record.ReadOnly = true;
            this.richTextBox_record.Size = new System.Drawing.Size(409, 186);
            this.richTextBox_record.TabIndex = 10;
            this.richTextBox_record.Text = "";
            // 
            // Server
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(549, 310);
            this.Controls.Add(this.richTextBox_record);
            this.Controls.Add(this.listView_userlist);
            this.Controls.Add(this.label3);
            this.Controls.Add(this.label2);
            this.Controls.Add(this.button_Send);
            this.Controls.Add(this.textBox_send);
            this.Controls.Add(this.label1);
            this.Controls.Add(this.textBox_port);
            this.Controls.Add(this.btnOpen);
            this.Name = "Server";
            this.Text = "服务器(TcpListener)";
            this.FormClosing += new System.Windows.Forms.FormClosingEventHandler(this.Server_FormClosing);
            this.ResumeLayout(false);
            this.PerformLayout();

        }

        #endregion

        private System.Windows.Forms.Button btnOpen;
        private System.Windows.Forms.TextBox textBox_port;
        private System.Windows.Forms.Label label1;
        private System.Windows.Forms.TextBox textBox_send;
        private System.Windows.Forms.Button button_Send;
        private System.Windows.Forms.Label label2;
        private System.Windows.Forms.Label label3;
        private System.Windows.Forms.ListView listView_userlist;
        private System.Windows.Forms.RichTextBox richTextBox_record;
    }
}

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

namespace SocketTest
{
    public partial class Server : Form
    {
        int selectIndex = 0;
        Thread serverThread;
        Thread clientThread;
        TcpListener listener;
        TcpClient clientTcp;
        Dictionary<IPHostEntry, TcpClient> userList = new Dictionary<IPHostEntry, TcpClient>();
        Encoding encoding = Encoding.UTF8;
        string record = "";
        string welcome = "Welcome to Sever ";
        bool isRun = true;
        public Server()
        {
            InitializeComponent();
        }

        private void ServerStart()
        {
            try
            {
                //创建IPEndPoint实例
                IPEndPoint ipep = new IPEndPoint(IPAddress.Any, int.Parse(textBox_port.Text));

                listener = new TcpListener(ipep);
                listener.Start(100);

                while (isRun)
                {
                    //在套接字上接收接入的连接
                    clientTcp = listener.AcceptTcpClient();
                    IPEndPoint temp = (IPEndPoint)clientTcp.Client.RemoteEndPoint;
                    IPHostEntry userpc = Dns.GetHostEntry(temp.Address);
                    AddUser(userpc, clientTcp);
                    clientThread = new Thread(new ThreadStart(ReceiveData));
                    clientThread.Start();
                }
                listener.Stop();
            }
            catch (Exception ex)
            {
                MessageBox.Show("listening Error: " + ex.Message);
            }
            finally
            {
                listener.Stop();
            }
        }

        private void ReceiveData()
        {
            TcpClient client = clientTcp;
            NetworkStream ns = client.GetStream();
            Byte[] buffer = new Byte[1024];

            //根据收听到的客户端套接字向客户端发送信息
            IPEndPoint ip = (IPEndPoint)client.Client.RemoteEndPoint;
            IPHostEntry userpc = Dns.GetHostEntry(ip.Address);

            record = Environment.NewLine + ip.Address + "(" + ip.Port + ") Connected!";
            ReshUI();
            byte[] data = new byte[1024];
            data = encoding.GetBytes(welcome);
            ns.Write(data, 0, data.Length);

            while (isRun)
            {
                //在套接字上接收客户端发送的信息
                int bufLen = 0;
                try
                {
                    bufLen = client.Available;
                    if (bufLen > 0)
                    {
                        ns.Read(buffer, 0, bufLen);
                        record = encoding.GetString(buffer).Substring(0, bufLen);
                        //保存接受消息
                        string message = string.Format("{0}{1}({2}):{3}    {4}", Environment.NewLine, Environment.UserName, DateTime.Now.ToString("HH:mm:ss"), Environment.NewLine, "Received");
                        ReshUI();
                        //反馈接受
                        WriteReceiveMessage(client, message);
                    }
                    if (bufLen == 0)
                        continue;
                }
                catch (Exception ex)
                {
                    MessageBox.Show("Receive Error:" + ex.Message);
                    return;
                }
            }
            client.Close();
        }

        void WriteReceiveMessage(TcpClient client, string message)
        {
            try
            {
                byte[] buffer = encoding.GetBytes(message);
                client.GetStream().Write(buffer, 0, buffer.Length);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message + "--" + ex.StackTrace);
            }
        }

        void AddUser(IPHostEntry userEntry, TcpClient tcpClient)
        {
            foreach (KeyValuePair<IPHostEntry, TcpClient> user in userList)
            {
                if (user.Value.Client.RemoteEndPoint.Equals(tcpClient.Client.RemoteEndPoint))
                    return;
            }
            userList.Add(userEntry, tcpClient);
            //listView1.Items.Add(ip);
        }

        string GetLocalIP()
        {
            string strHostIP = "";
            IPHostEntry oIPHost = Dns.GetHostEntry(Environment.MachineName);
            if (oIPHost.AddressList.Length > 0)
                strHostIP = oIPHost.AddressList[0].ToString();
            return strHostIP;
        }

        void ReshUI()
        {

            //while (true)
            //{
            MethodInvoker mi = new MethodInvoker(ShowUIData);
            this.Invoke(mi);
            Thread.Sleep(500);
            //}
        }

        void ShowUIData()
        {
            richTextBox_record.Text += record;
            listView_userlist.Items.Clear();
            foreach (KeyValuePair<IPHostEntry, TcpClient> kp in userList)
            {
                if (!kp.Value.Client.Connected)
                {
                    userList.Remove(kp.Key);
                    continue;
                }
                IPEndPoint temp = (IPEndPoint)kp.Value.Client.RemoteEndPoint;
                ListViewItem lvi = new ListViewItem(kp.Key.HostName + "(" + temp.Port + ")");
                lvi.Tag = temp;
                listView_userlist.Items.Add(lvi);

            }
            if (listView_userlist.Items.Count > 0)
            {
                listView_userlist.Items[selectIndex].Checked = true;
                listView_userlist.Items[selectIndex].Selected = true;
                listView_userlist.EnsureVisible(selectIndex);
                listView_userlist.HideSelection = false;
            }
            record = "";

            richTextBox_record.SelectionStart = richTextBox_record.TextLength > 0 ? richTextBox_record.TextLength - 1 : 0;
            richTextBox_record.SelectionLength = 0;
        }

        private void listView_userlist_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (listView_userlist.Items.Count > 0 && listView_userlist.SelectedItems.Count > 0)
                selectIndex = listView_userlist.SelectedItems[0].Index;
        }

        private void btnOpen_Click(object sender, EventArgs e)
        {
            try
            {
                //if (listener != null)
                //{
                //    try
                //    {
                //        isRun = false;
                //        if (clientTcp != null)
                //        {
                //            clientTcp.Close();
                //            clientTcp.Client.Shutdown(SocketShutdown.Both);
                //            clientTcp.Client.Close();
                //        }
                //        listener.Server.Close();
                //        listener.Server.Shutdown(SocketShutdown.Both);
                //        listener.Server.Close();
                //        listener.Stop();
                //    }
                //    finally
                //    {
                //        clientTcp.Close();
                //        listener.Stop();
                //    }
                //}
                //else
                //{
                serverThread = new Thread(new ThreadStart(ServerStart));
                serverThread.Start();
                richTextBox_record.Text += Environment.NewLine + "----Server Start ...----";
                Thread ui = new Thread(new ThreadStart(ReshUI));
                ui.Start();
                button_Send.Enabled = true;
                //btnOpen.Enabled = false;
                //}
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        void ToLastPosition()
        {

        }

        private void Server_FormClosing(object sender, FormClosingEventArgs e)
        {
            Environment.Exit(0);
        }

        private void textBox2_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (e.KeyChar == (char)Keys.Enter)
            {
                button_Send_Click(null, null);
                e.Handled = true;

            }
        }

        private void button_Send_Click(object sender, EventArgs e)
        {
            if (textBox_send.Text.Length > 0)
            {
                if (listView_userlist.SelectedItems.Count < 1)
                {
                    MessageBox.Show("请选择要通信的IP");
                    return;
                }
                string message = Environment.NewLine + string.Format("{0}({1}):{2}    {3}", Environment.UserName, DateTime.Now.ToString("HH:mm:ss"), Environment.NewLine, textBox_send.Text);
                richTextBox_record.Text += message;
                richTextBox_record.SelectionStart = richTextBox_record.TextLength > 0 ? richTextBox_record.TextLength - 1 : 0;
                richTextBox_record.SelectionLength = 0;
                textBox_send.Clear();
                textBox_send.Focus();
                foreach (ListViewItem li in listView_userlist.SelectedItems)
                {
                    foreach (KeyValuePair<IPHostEntry, TcpClient> kp in userList)
                    {
                        //(EndPoint)li.Tag;
                        if (li.Tag.Equals(kp.Value.Client.RemoteEndPoint))
                        {
                            WriteReceiveMessage(kp.Value, message);
                        }
                    }
                }

            }
        }
    }
}

 

namespace Client
{
    partial class Client
    {
        /// <summary>
        /// 必需的设计器变量。
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// 清理所有正在使用的资源。
        /// </summary>
        /// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (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.textBox_send = new System.Windows.Forms.TextBox();
            this.btnSend = new System.Windows.Forms.Button();
            this.linkLabel_connect = new System.Windows.Forms.LinkLabel();
            this.label1 = new System.Windows.Forms.Label();
            this.label2 = new System.Windows.Forms.Label();
            this.textBox2 = new System.Windows.Forms.TextBox();
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.richTextBox_record = new System.Windows.Forms.RichTextBox();
            this.SuspendLayout();
            // 
            // textBox_send
            // 
            this.textBox_send.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)
                        | System.Windows.Forms.AnchorStyles.Right)));
            this.textBox_send.Location = new System.Drawing.Point(12, 223);
            this.textBox_send.Multiline = true;
            this.textBox_send.Name = "textBox_send";
            this.textBox_send.ScrollBars = System.Windows.Forms.ScrollBars.Vertical;
            this.textBox_send.Size = new System.Drawing.Size(425, 45);
            this.textBox_send.TabIndex = 1;
            this.textBox_send.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.txtClient_KeyPress);
            // 
            // btnSend
            // 
            this.btnSend.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right)));
            this.btnSend.Enabled = false;
            this.btnSend.Location = new System.Drawing.Point(443, 223);
            this.btnSend.Name = "btnSend";
            this.btnSend.Size = new System.Drawing.Size(44, 45);
            this.btnSend.TabIndex = 2;
            this.btnSend.Text = "发送信息";
            this.btnSend.UseVisualStyleBackColor = true;
            this.btnSend.Click += new System.EventHandler(this.btnSend_Click);
            // 
            // linkLabel_connect
            // 
            this.linkLabel_connect.AutoSize = true;
            this.linkLabel_connect.Location = new System.Drawing.Point(420, 9);
            this.linkLabel_connect.Name = "linkLabel_connect";
            this.linkLabel_connect.Size = new System.Drawing.Size(67, 13);
            this.linkLabel_connect.TabIndex = 4;
            this.linkLabel_connect.TabStop = true;
            this.linkLabel_connect.Text = "连接服务器";
            this.linkLabel_connect.LinkClicked += new System.Windows.Forms.LinkLabelLinkClickedEventHandler(this.linkLabel_connect_LinkClicked);
            // 
            // label1
            // 
            this.label1.AutoSize = true;
            this.label1.Location = new System.Drawing.Point(12, 9);
            this.label1.Name = "label1";
            this.label1.Size = new System.Drawing.Size(29, 13);
            this.label1.TabIndex = 5;
            this.label1.Text = "IP：";
            // 
            // label2
            // 
            this.label2.AutoSize = true;
            this.label2.Location = new System.Drawing.Point(145, 9);
            this.label2.Name = "label2";
            this.label2.Size = new System.Drawing.Size(43, 13);
            this.label2.TabIndex = 7;
            this.label2.Text = "端口：";
            // 
            // textBox2
            // 
            this.textBox2.Location = new System.Drawing.Point(194, 6);
            this.textBox2.Name = "textBox2";
            this.textBox2.Size = new System.Drawing.Size(65, 20);
            this.textBox2.TabIndex = 8;
            this.textBox2.Text = "2001";
            // 
            // textBox1
            // 
            this.textBox1.Location = new System.Drawing.Point(39, 6);
            this.textBox1.Name = "textBox1";
            this.textBox1.Size = new System.Drawing.Size(100, 20);
            this.textBox1.TabIndex = 9;
            this.textBox1.Text = "172.21.140.142";
            // 
            // richTextBox_record
            // 
            this.richTextBox_record.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)
                        | System.Windows.Forms.AnchorStyles.Left)
                        | System.Windows.Forms.AnchorStyles.Right)));
            this.richTextBox_record.BackColor = System.Drawing.SystemColors.Window;
            this.richTextBox_record.HideSelection = false;
            this.richTextBox_record.Location = new System.Drawing.Point(12, 32);
            this.richTextBox_record.Name = "richTextBox_record";
            this.richTextBox_record.ReadOnly = true;
            this.richTextBox_record.Size = new System.Drawing.Size(475, 185);
            this.richTextBox_record.TabIndex = 10;
            this.richTextBox_record.Text = "";
            // 
            // Client
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(499, 288);
            this.Controls.Add(this.richTextBox_record);
            this.Controls.Add(this.textBox1);
            this.Controls.Add(this.textBox2);
            this.Controls.Add(this.label2);
            this.Controls.Add(this.label1);
            this.Controls.Add(this.linkLabel_connect);
            this.Controls.Add(this.btnSend);
            this.Controls.Add(this.textBox_send);
            this.Name = "Client";
            this.Text = "客户端(TcpClient)";
            this.FormClosing += new System.Windows.Forms.FormClosingEventHandler(this.Client_FormClosing);
            this.ResumeLayout(false);
            this.PerformLayout();

        }

        #endregion

        private System.Windows.Forms.TextBox textBox_send;
        private System.Windows.Forms.Button btnSend;
        private System.Windows.Forms.LinkLabel linkLabel_connect;
        private System.Windows.Forms.Label label1;
        private System.Windows.Forms.Label label2;
        private System.Windows.Forms.TextBox textBox2;
        private System.Windows.Forms.TextBox textBox1;
        private System.Windows.Forms.RichTextBox richTextBox_record;
    }
}

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.Net.Sockets;
using System.Threading;

namespace Client
{
    public partial class Client : Form
    {
        TcpClient clientTcp;
        Thread clientThread;
        IPEndPoint serverIP;
        IPHostEntry serverPc;
        NetworkStream ns;
        string ReceiveData = "";
        Encoding encoding = Encoding.UTF8;

        public Client()
        {
            InitializeComponent();
        }

        private void ConnectToServer()
        {
            byte[] data = new byte[1024];
            ns = clientTcp.GetStream();
            serverIP = (IPEndPoint)clientTcp.Client.RemoteEndPoint;
            serverPc = Dns.GetHostEntry(serverIP.Address);
            while (true)
            {
                //接收服务器信息
                int bufLen = 0;
                try
                {
                    bufLen = clientTcp.Available;

                    ns.Read(data, 0, bufLen);
                    if (bufLen == 0)
                    {
                        continue;
                    }
                }
                catch (Exception ex)
                {
                    MessageBox.Show("Receive Error:" + ex.Message);
                    return;
                }
                ReceiveData = encoding.GetString(data).Substring(0, bufLen);
                ReshUI();
            }
        }

        void ReshUI()
        {
            //while (true)
            //{
            //Thread.Sleep(500);
            MethodInvoker mi = new MethodInvoker(ShowUIData);
            this.Invoke(mi);
            //}
        }

        void ShowUIData()
        {
            if (ReceiveData.Length > 0)
            {
                richTextBox_record.Text += ReceiveData;
                ReceiveData = "";
            }
            if (clientTcp.Connected)
                linkLabel_connect.Enabled = false;
            else
                linkLabel_connect.Enabled = true;
            richTextBox_record.SelectionStart = richTextBox_record.TextLength > 0 ? richTextBox_record.TextLength - 1 : 0;
            richTextBox_record.SelectionLength = 0;
        }

        string GetLocalIP()
        {
            string strHostIP = "";
            IPHostEntry oIPHost = Dns.GetHostEntry(Environment.MachineName);
            if (oIPHost.AddressList.Length > 0)
                strHostIP = oIPHost.AddressList[0].ToString();
            return strHostIP;
        }


        private void btnSend_Click(object sender, EventArgs e)
        {
            if (textBox_send.Text.Length > 0)
            {
                string message = string.Format("{0}{1}({2}):{3}    {4}", Environment.NewLine, Environment.UserName, DateTime.Now.ToString("HH:mm:ss"), Environment.NewLine, textBox_send.Text);
                richTextBox_record.Text += message;
                richTextBox_record.SelectionStart = richTextBox_record.TextLength > 0 ? richTextBox_record.TextLength - 1 : 0;
                richTextBox_record.SelectionLength = 0;
                textBox_send.Clear();
                textBox_send.Focus();
                //向服务器发送信息 
                byte[] data = encoding.GetBytes(message);
                ns.Write(data, 0, data.Length);


            }
        }

        private void linkLabel_connect_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
        {
            //创建一个套接字
            IPEndPoint ipep = new IPEndPoint(IPAddress.Parse(textBox1.Text), int.Parse(textBox2.Text));
            clientTcp = new TcpClient();

            //将套接字与远程服务器地址相连
            try
            {
                clientTcp.Connect(ipep);
                clientThread = new Thread(new ThreadStart(ConnectToServer));
                clientThread.Start();
                Thread ui = new Thread(new ThreadStart(ReshUI));
                ui.Start();
                btnSend.Enabled = true;
            }
            catch (SocketException ex)
            {
                MessageBox.Show("connect error: " + ex.Message);
                return;
            }

        }

        private void Client_FormClosing(object sender, FormClosingEventArgs e)
        {
            Environment.Exit(0);
        }

        private void txtClient_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (e.KeyChar == (char)Keys.Enter)
            {
                btnSend_Click(null, null);
                e.Handled = true;
            }
        }
    }
}