C#实现将聊天数据发送加密

public partial class FORM1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    #region 定义全局对象及变量
    private IPEndPoint Server;//服务器端
    private IPEndPoint Client;//客户端
    private Socket mySocket;//套接字
    private EndPoint ClientIP;//IP地址
    byte[] buffer, data;//接收缓存
    bool blFlag = true;//标识是否第一次发送信息
    bool ISPort = false;//判断端口打开
    int SendNum1, ReceiveNum1, DisNum1; //记录窗体加载时的已发送\已接收\丢失的数据报
    int SendNum2, ReceiveNum2, DisNum2; //记录当前已发送\已接收\丢失的数据报
    int SendNum3, ReceiveNum3, DisNum3; //缓存已发送\已接收\丢失的数据报
    int port;//端口号
    #endregion

    //异步接收信息
    private void StartLister(IAsyncResult IAResult)
    {
        int Num = mySocket.EndReceiveFrom(IAResult, ref ClientIP);
        string strInfo = Encoding.Unicode.GetString(buffer, 0, Num);
        rtbContent.AppendText("用户" + ClientIP.ToString());
        rtbContent.AppendText("：");
        rtbContent.AppendText("\r\n");
        rtbContent.AppendText(DecryptDES(strInfo, "mrsoftxk"));//对接收到的信息进行解密
        rtbContent.AppendText("\r\n");
        mySocket.BeginReceiveFrom(buffer, 0, buffer.Length, SocketFlags.None, ref ClientIP, new AsyncCallback(StartLister), null);
    }

    //初始化已发送、已接收和丢失的数据报
    private void Form1_Load(object sender, EventArgs e)
    {
        if (blFlag == true)
        {
            IPGlobalProperties NetInfo = IPGlobalProperties.GetIPGlobalProperties();
            UdpStatistics myUdpStat = null;
            myUdpStat = NetInfo.GetUdpIPv4Statistics();
            SendNum1 = Int32.Parse(myUdpStat.DatagramsSent.ToString());
            ReceiveNum1 = Int32.Parse(myUdpStat.DatagramsReceived.ToString());
            DisNum1 = Int32.Parse(myUdpStat.IncomingDatagramsDiscarded.ToString());
        }
    }

    //设置端口号
    private void button4_Click(object sender, EventArgs e)
    {
        try
        {
            port = Convert.ToInt32(textBox4.Text);
            CheckForIllegalCrossThreadCalls = false;
            buffer = new byte[1024];
            data = new byte[1024];
            Server = new IPEndPoint(IPAddress.Any, port);
            Client = new IPEndPoint(IPAddress.Broadcast, port);
            ClientIP = (EndPoint)Server;
            mySocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
            mySocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.Broadcast, 1);
            mySocket.Bind(Server);
            mySocket.BeginReceiveFrom(buffer, 0, buffer.Length, SocketFlags.None, ref ClientIP, new AsyncCallback(StartLister), null);
            ISPort = true;//打开指定端口号
        }
        catch { }
    }

    //发送信息
    private void button2_Click(object sender, EventArgs e)
    {
        if (ISPort == true)//判断是否有打开的端口号
        {
            IPGlobalProperties NetInfo = IPGlobalProperties.GetIPGlobalProperties();
            UdpStatistics myUdpStat = null;
            myUdpStat = NetInfo.GetUdpIPv4Statistics();
            try
            {
                if (blFlag == false)//非第一次发送
                {
                    SendNum2 = Int32.Parse(myUdpStat.DatagramsSent.ToString());
                    ReceiveNum2 = Int32.Parse(myUdpStat.DatagramsReceived.ToString());
                    DisNum2 = Int32.Parse(myUdpStat.IncomingDatagramsDiscarded.ToString());
                    textBox1.Text = Convert.ToString(SendNum2 - SendNum3);
                    textBox2.Text = Convert.ToString(ReceiveNum2 - ReceiveNum3);
                    textBox3.Text = Convert.ToString(DisNum2 - DisNum3);
                }
                SendNum2 = Int32.Parse(myUdpStat.DatagramsSent.ToString());
                ReceiveNum2 = Int32.Parse(myUdpStat.DatagramsReceived.ToString());
                DisNum2 = Int32.Parse(myUdpStat.IncomingDatagramsDiscarded.ToString());
                SendNum3 = SendNum2; //记录本次的发送数据报
                ReceiveNum3 = ReceiveNum2;//记录本次的接收数据报
                DisNum3 = DisNum2; //记录本次的丢失数据报
                if (blFlag == true)//第一次发送
                {
                    textBox1.Text = Convert.ToString(SendNum2 - SendNum1);
                    textBox2.Text = Convert.ToString(ReceiveNum2 - ReceiveNum1);
                    textBox3.Text = Convert.ToString(DisNum2 - DisNum1);
                    blFlag = false;
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "提示信息", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
            string str = EncryptDES(rtbSend.Text, "mrsoftxk");//加密要发送的信息
            data = Encoding.Unicode.GetBytes(str);
            mySocket.SendTo(data, data.Length, SocketFlags.None, Client);
            rtbSend.Text = "";
        }
        else
        {
            MessageBox.Show("请首先打开端口！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
            button4.Focus();
        }
    }

    //清屏
    private void button1_Click(object sender, EventArgs e)
    {
        rtbContent.Clear();
    }

    //退出
    private void button3_Click(object sender, EventArgs e)
    {
        Application.Exit();
    }

    //按<Ctrl+Enter>组合键发送信息
    private void rtbSend_KeyDown(object sender, KeyEventArgs e)
    {
        //当同时按下Ctrl和Enter时，发送消息
        if (e.Control && e.KeyValue == 13)
        {
            e.Handled = true;
            button2_Click(this, null);
        }
    }

    //聊天记录随时滚动
    private void rtbContent_TextChanged(object sender, EventArgs e)
    {
        rtbContent.ScrollToCaret();
    }

    private static byte[] Keys = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };//密钥

    #region DES加密字符串
    ///<summary>   
    ///DES加密字符串   
    ///</summary>   
    ///<param name="str">待加密的字符串</param>   
    ///<param name="key">加密密钥,要求为8位</param>   
    ///<returns>加密成功返回加密后的字符串，失败返回源字符串</returns>   
    public string EncryptDES(string str, string key)
    {
        try
        {
            byte[] rgbKey = Encoding.UTF8.GetBytes(key.Substring(0, 8));
            byte[] rgbIV = Keys;
            byte[] inputByteArray = Encoding.UTF8.GetBytes(str);
            DESCryptoServiceProvider myDES = new DESCryptoServiceProvider();
            MemoryStream MStream = new MemoryStream();
            CryptoStream CStream = new CryptoStream(MStream, myDES.CreateEncryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
            CStream.Write(inputByteArray, 0, inputByteArray.Length);
            CStream.FlushFinalBlock();
            return Convert.ToBase64String(MStream.ToArray());
        }
        catch
        {
            return str;
        }
    }
    #endregion

    #region DES解密字符串
    ///<summary>   
    ///DES解密字符串   
    ///</summary>   
    ///<param name="str">待解密的字符串</param>   
    ///<param name="key">解密密钥,要求为8位,和加密密钥相同</param>   
    ///<returns>解密成功返回解密后的字符串，失败返源字符串</returns>   
    public string DecryptDES(string str, string key)
    {
        try
        {
            byte[] rgbKey = Encoding.UTF8.GetBytes(key);
            byte[] rgbIV = Keys;
            byte[] inputByteArray = Convert.FromBase64String(str);
            DESCryptoServiceProvider myDES = new DESCryptoServiceProvider();
            MemoryStream MStream = new MemoryStream();
            CryptoStream CStream = new CryptoStream(MStream, myDES.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
            CStream.Write(inputByteArray, 0, inputByteArray.Length);
            CStream.FlushFinalBlock();
            return Encoding.UTF8.GetString(MStream.ToArray());
        }
        catch
        {
            return str;
        }
    }
    #endregion
}

partial class Form1
{
    /// <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.splitContainer1 = new System.Windows.Forms.SplitContainer();
        this.rtbContent = new System.Windows.Forms.RichTextBox();
        this.splitContainer2 = new System.Windows.Forms.SplitContainer();
        this.rtbSend = new System.Windows.Forms.RichTextBox();
        this.button1 = new System.Windows.Forms.Button();
        this.button2 = new System.Windows.Forms.Button();
        this.button3 = new System.Windows.Forms.Button();
        this.groupBox1 = new System.Windows.Forms.GroupBox();
        this.textBox3 = new System.Windows.Forms.TextBox();
        this.label5 = new System.Windows.Forms.Label();
        this.textBox2 = new System.Windows.Forms.TextBox();
        this.label4 = new System.Windows.Forms.Label();
        this.textBox1 = new System.Windows.Forms.TextBox();
        this.label3 = new System.Windows.Forms.Label();
        this.label8 = new System.Windows.Forms.Label();
        this.textBox4 = new System.Windows.Forms.TextBox();
        this.groupBox2 = new System.Windows.Forms.GroupBox();
        this.button4 = new System.Windows.Forms.Button();
        this.splitContainer1.Panel1.SuspendLayout();
        this.splitContainer1.Panel2.SuspendLayout();
        this.splitContainer1.SuspendLayout();
        this.splitContainer2.Panel1.SuspendLayout();
        this.splitContainer2.Panel2.SuspendLayout();
        this.splitContainer2.SuspendLayout();
        this.groupBox1.SuspendLayout();
        this.groupBox2.SuspendLayout();
        this.SuspendLayout();
        // 
        // splitContainer1
        // 
        this.splitContainer1.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
        this.splitContainer1.Location = new System.Drawing.Point(4, 4);
        this.splitContainer1.Name = "splitContainer1";
        this.splitContainer1.Orientation = System.Windows.Forms.Orientation.Horizontal;
        // 
        // splitContainer1.Panel1
        // 
        this.splitContainer1.Panel1.Controls.Add(this.rtbContent);
        // 
        // splitContainer1.Panel2
        // 
        this.splitContainer1.Panel2.Controls.Add(this.splitContainer2);
        this.splitContainer1.Size = new System.Drawing.Size(430, 364);
        this.splitContainer1.SplitterDistance = 240;
        this.splitContainer1.SplitterWidth = 3;
        this.splitContainer1.TabIndex = 1;
        // 
        // rtbContent
        // 
        this.rtbContent.BackColor = System.Drawing.Color.White;
        this.rtbContent.BorderStyle = System.Windows.Forms.BorderStyle.None;
        this.rtbContent.Dock = System.Windows.Forms.DockStyle.Fill;
        this.rtbContent.Location = new System.Drawing.Point(0, 0);
        this.rtbContent.Name = "rtbContent";
        this.rtbContent.ReadOnly = true;
        this.rtbContent.Size = new System.Drawing.Size(428, 238);
        this.rtbContent.TabIndex = 9;
        this.rtbContent.Text = "";
        this.rtbContent.TextChanged += new System.EventHandler(this.rtbContent_TextChanged);
        // 
        // splitContainer2
        // 
        this.splitContainer2.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
        this.splitContainer2.Dock = System.Windows.Forms.DockStyle.Fill;
        this.splitContainer2.Location = new System.Drawing.Point(0, 0);
        this.splitContainer2.Name = "splitContainer2";
        this.splitContainer2.Orientation = System.Windows.Forms.Orientation.Horizontal;
        // 
        // splitContainer2.Panel1
        // 
        this.splitContainer2.Panel1.Controls.Add(this.rtbSend);
        // 
        // splitContainer2.Panel2
        // 
        this.splitContainer2.Panel2.Controls.Add(this.button1);
        this.splitContainer2.Panel2.Controls.Add(this.button2);
        this.splitContainer2.Panel2.Controls.Add(this.button3);
        this.splitContainer2.Size = new System.Drawing.Size(430, 121);
        this.splitContainer2.SplitterDistance = 87;
        this.splitContainer2.SplitterWidth = 1;
        this.splitContainer2.TabIndex = 0;
        // 
        // rtbSend
        // 
        this.rtbSend.BorderStyle = System.Windows.Forms.BorderStyle.None;
        this.rtbSend.Dock = System.Windows.Forms.DockStyle.Fill;
        this.rtbSend.Location = new System.Drawing.Point(0, 0);
        this.rtbSend.Name = "rtbSend";
        this.rtbSend.Size = new System.Drawing.Size(428, 85);
        this.rtbSend.TabIndex = 2;
        this.rtbSend.Text = "";
        this.rtbSend.KeyDown += new System.Windows.Forms.KeyEventHandler(this.rtbSend_KeyDown);
        // 
        // button1
        // 
        this.button1.Location = new System.Drawing.Point(294, 4);
        this.button1.Name = "button1";
        this.button1.Size = new System.Drawing.Size(39, 23);
        this.button1.TabIndex = 4;
        this.button1.Text = "清屏";
        this.button1.UseVisualStyleBackColor = true;
        this.button1.Click += new System.EventHandler(this.button1_Click);
        // 
        // button2
        // 
        this.button2.Location = new System.Drawing.Point(339, 4);
        this.button2.Name = "button2";
        this.button2.Size = new System.Drawing.Size(38, 23);
        this.button2.TabIndex = 3;
        this.button2.Text = "发送";
        this.button2.UseVisualStyleBackColor = true;
        this.button2.Click += new System.EventHandler(this.button2_Click);
        // 
        // button3
        // 
        this.button3.Location = new System.Drawing.Point(383, 4);
        this.button3.Name = "button3";
        this.button3.Size = new System.Drawing.Size(39, 23);
        this.button3.TabIndex = 5;
        this.button3.Text = "关闭";
        this.button3.UseVisualStyleBackColor = true;
        this.button3.Click += new System.EventHandler(this.button3_Click);
        // 
        // groupBox1
        // 
        this.groupBox1.Controls.Add(this.textBox3);
        this.groupBox1.Controls.Add(this.label5);
        this.groupBox1.Controls.Add(this.textBox2);
        this.groupBox1.Controls.Add(this.label4);
        this.groupBox1.Controls.Add(this.textBox1);
        this.groupBox1.Controls.Add(this.label3);
        this.groupBox1.Location = new System.Drawing.Point(440, 87);
        this.groupBox1.Name = "groupBox1";
        this.groupBox1.Size = new System.Drawing.Size(109, 165);
        this.groupBox1.TabIndex = 8;
        this.groupBox1.TabStop = false;
        this.groupBox1.Text = "数据传输信息";
        // 
        // textBox3
        // 
        this.textBox3.Location = new System.Drawing.Point(20, 132);
        this.textBox3.Name = "textBox3";
        this.textBox3.ReadOnly = true;
        this.textBox3.Size = new System.Drawing.Size(77, 21);
        this.textBox3.TabIndex = 7;
        // 
        // label5
        // 
        this.label5.AutoSize = true;
        this.label5.Location = new System.Drawing.Point(8, 115);
        this.label5.Name = "label5";
        this.label5.Size = new System.Drawing.Size(77, 12);
        this.label5.TabIndex = 6;
        this.label5.Text = "丢失数据报：";
        // 
        // textBox2
        // 
        this.textBox2.Location = new System.Drawing.Point(20, 86);
        this.textBox2.Name = "textBox2";
        this.textBox2.ReadOnly = true;
        this.textBox2.Size = new System.Drawing.Size(77, 21);
        this.textBox2.TabIndex = 7;
        // 
        // label4
        // 
        this.label4.AutoSize = true;
        this.label4.Location = new System.Drawing.Point(8, 69);
        this.label4.Name = "label4";
        this.label4.Size = new System.Drawing.Size(89, 12);
        this.label4.TabIndex = 4;
        this.label4.Text = "已接收数据报：";
        // 
        // textBox1
        // 
        this.textBox1.Location = new System.Drawing.Point(20, 40);
        this.textBox1.Name = "textBox1";
        this.textBox1.ReadOnly = true;
        this.textBox1.Size = new System.Drawing.Size(77, 21);
        this.textBox1.TabIndex = 6;
        // 
        // label3
        // 
        this.label3.AutoSize = true;
        this.label3.Location = new System.Drawing.Point(8, 23);
        this.label3.Name = "label3";
        this.label3.Size = new System.Drawing.Size(89, 12);
        this.label3.TabIndex = 2;
        this.label3.Text = "已发送数据报：";
        // 
        // label8
        // 
        this.label8.AutoSize = true;
        this.label8.Location = new System.Drawing.Point(8, 23);
        this.label8.Name = "label8";
        this.label8.Size = new System.Drawing.Size(53, 12);
        this.label8.TabIndex = 2;
        this.label8.Text = "端口号：";
        // 
        // textBox4
        // 
        this.textBox4.Location = new System.Drawing.Point(20, 40);
        this.textBox4.Name = "textBox4";
        this.textBox4.Size = new System.Drawing.Size(77, 21);
        this.textBox4.TabIndex = 0;
        this.textBox4.Text = "8888";
        // 
        // groupBox2
        // 
        this.groupBox2.Controls.Add(this.button4);
        this.groupBox2.Controls.Add(this.textBox4);
        this.groupBox2.Controls.Add(this.label8);
        this.groupBox2.Location = new System.Drawing.Point(440, 258);
        this.groupBox2.Name = "groupBox2";
        this.groupBox2.Size = new System.Drawing.Size(109, 110);
        this.groupBox2.TabIndex = 2;
        this.groupBox2.TabStop = false;
        this.groupBox2.Text = "端口设置";
        // 
        // button4
        // 
        this.button4.Location = new System.Drawing.Point(22, 68);
        this.button4.Name = "button4";
        this.button4.Size = new System.Drawing.Size(75, 32);
        this.button4.TabIndex = 1;
        this.button4.Text = "设置";
        this.button4.UseVisualStyleBackColor = true;
        this.button4.Click += new System.EventHandler(this.button4_Click);
        // 
        // Form1
        // 
        this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
        this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
        this.ClientSize = new System.Drawing.Size(555, 372);
        this.Controls.Add(this.groupBox2);
        this.Controls.Add(this.groupBox1);
        this.Controls.Add(this.splitContainer1);
        this.Name = "Form1";
        this.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen;
        this.Text = "对数据报进行加密保障通信完全";
        this.Load += new System.EventHandler(this.Form1_Load);
        this.splitContainer1.Panel1.ResumeLayout(false);
        this.splitContainer1.Panel2.ResumeLayout(false);
        this.splitContainer1.ResumeLayout(false);
        this.splitContainer2.Panel1.ResumeLayout(false);
        this.splitContainer2.Panel2.ResumeLayout(false);
        this.splitContainer2.ResumeLayout(false);
        this.groupBox1.ResumeLayout(false);
        this.groupBox1.PerformLayout();
        this.groupBox2.ResumeLayout(false);
        this.groupBox2.PerformLayout();
        this.ResumeLayout(false);

    }

    #endregion

    private System.Windows.Forms.SplitContainer splitContainer1;
    private System.Windows.Forms.RichTextBox rtbContent;
    private System.Windows.Forms.SplitContainer splitContainer2;
    private System.Windows.Forms.RichTextBox rtbSend;
    private System.Windows.Forms.Button button1;
    private System.Windows.Forms.Button button2;
    private System.Windows.Forms.Button button3;
    private System.Windows.Forms.GroupBox groupBox1;
    private System.Windows.Forms.TextBox textBox3;
    private System.Windows.Forms.Label label5;
    private System.Windows.Forms.TextBox textBox2;
    private System.Windows.Forms.Label label4;
    private System.Windows.Forms.TextBox textBox1;
    private System.Windows.Forms.Label label3;
    private System.Windows.Forms.Label label8;
    private System.Windows.Forms.TextBox textBox4;
    private System.Windows.Forms.GroupBox groupBox2;
    private System.Windows.Forms.Button button4;
}