一個綠色免安裝軟件，領導臨時要求加個注冊機制，不能讓現場工程師隨意復制。事出突然,只能在現場開發（離開現場軟件就不受我們控了）。花了不到兩個小時實現了簡單的注冊機制，稍作整理。 
基本原理：1.軟件一運行就把計算機的CPU、主板、BIOS、MAC地址記錄下來，然后加密（key=key1）生成文件；2.注冊機將該文件內容MD5加密后再進行一次加密(key=key2)保存成注冊文件；3.注冊驗證的邏輯，計算機信息加密后（key=key1）加密md5==注冊文件解密（key=key2）； 
另外，采用ConfuserEx將可執行文件加密；這樣別人要破解也就需要點力氣了（沒打算防破解，本意只想防復制的），有能力破解的人也不在乎破解這個軟件了（開發這個軟件前后只花了一周時間而已）； 

技術上主要三個模塊：1.獲取電腦相關硬件信息(可參考)；2.加密解密；3.讀寫文件；

1.獲取電腦相關硬件信息代碼：

public class ComputerInfo
{
    public static string GetComputerInfo()
    {
        string info = string.Empty;
        string cpu = GetCPUInfo();
        string baseBoard = GetBaseBoardInfo();
        string bios = GetBIOSInfo();
        string mac = GetMACInfo();
        info = string.Concat(cpu, baseBoard, bios, mac);
        return info;
    }

    private static string GetCPUInfo()
    {
        string info = string.Empty;
        info = GetHardWareInfo("Win32_Processor", "ProcessorId");
        return info;
    }
    private static string GetBIOSInfo()
    {
        string info = string.Empty;
        info = GetHardWareInfo("Win32_BIOS", "SerialNumber");
        return info;
    }
    private static string GetBaseBoardInfo()
    {
        string info = string.Empty;
        info = GetHardWareInfo("Win32_BaseBoard", "SerialNumber");
        return info;
    }
    private static string GetMACInfo()
    {
        string info = string.Empty;
        info = GetHardWareInfo("Win32_BaseBoard", "SerialNumber");
        return info;
    }
    private static string GetHardWareInfo(string typePath, string key)
    {
        try
        {
            ManagementClass managementClass = new ManagementClass(typePath);
            ManagementObjectCollection mn = managementClass.GetInstances();
            PropertyDataCollection properties = managementClass.Properties;
            foreach (PropertyData property in properties)
            {
                if (property.Name == key)
                {
                    foreach (ManagementObject m in mn)
                    {
                        return m.Properties[property.Name].Value.ToString();
                    }
                }

            }
        }
        catch (Exception ex)
        {
            //這里寫異常的處理  
        }
        return string.Empty;
    }
    private static string GetMacAddressByNetworkInformation()
    {
        string key = "SYSTEM\\CurrentControlSet\\Control\\Network\\{4D36E972-E325-11CE-BFC1-08002BE10318}\\";
        string macAddress = string.Empty;
        try
        {
            NetworkInterface[] nics = NetworkInterface.GetAllNetworkInterfaces();
            foreach (NetworkInterface adapter in nics)
            {
                if (adapter.NetworkInterfaceType == NetworkInterfaceType.Ethernet
                    && adapter.GetPhysicalAddress().ToString().Length != 0)
                {
                    string fRegistryKey = key + adapter.Id + "\\Connection";
                    RegistryKey rk = Registry.LocalMachine.OpenSubKey(fRegistryKey, false);
                    if (rk != null)
                    {
                        string fPnpInstanceID = rk.GetValue("PnpInstanceID", "").ToString();
                        int fMediaSubType = Convert.ToInt32(rk.GetValue("MediaSubType", 0));
                        if (fPnpInstanceID.Length > 3 &&
                            fPnpInstanceID.Substring(0, 3) == "PCI")
                        {
                            macAddress = adapter.GetPhysicalAddress().ToString();
                            for (int i = 1; i < 6; i++)
                            {
                                macAddress = macAddress.Insert(3 * i - 1, ":");
                            }
                            break;
                        }
                    }

                }
            }
        }
        catch (Exception ex)
        {
            //這里寫異常的處理  
        }
        return macAddress;
    }
}

  2.加密解密代碼；

public enum EncryptionKeyEnum
{
    KeyA,
    KeyB
}
public class EncryptionHelper
{
    string encryptionKeyA = "pfe_Nova";
    string encryptionKeyB = "WorkHard";
    string md5Begin = "Hello";
    string md5End = "World";
    string encryptionKey = string.Empty;
    public EncryptionHelper()
    {
        this.InitKey();
    }
    public EncryptionHelper(EncryptionKeyEnum key)
    {
        this.InitKey(key);
    }
    private void InitKey(EncryptionKeyEnum key = EncryptionKeyEnum.KeyA)
    {
        switch (key)
        {
            case EncryptionKeyEnum.KeyA:
                encryptionKey = encryptionKeyA;
                break;
            case EncryptionKeyEnum.KeyB:
                encryptionKey = encryptionKeyB;
                break;
        }
    }

    public string EncryptString(string str)
    {
        return Encrypt(str, encryptionKey);
    }
    public string DecryptString(string str)
    {
        return Decrypt(str, encryptionKey);
    }
    public string GetMD5String(string str)
    {
        str = string.Concat(md5Begin, str, md5End);
        MD5 md5 = new MD5CryptoServiceProvider();
        byte[] fromData = Encoding.Unicode.GetBytes(str);
        byte[] targetData = md5.ComputeHash(fromData);
        string md5String = string.Empty;
        foreach (var b in targetData)
            md5String += b.ToString("x2");
        return md5String;
    }

    private string Encrypt(string str, string sKey)
    {
        DESCryptoServiceProvider des = new DESCryptoServiceProvider();
        byte[] inputByteArray = Encoding.Default.GetBytes(str);
        des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
        des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
        MemoryStream ms = new MemoryStream();
        CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);
        cs.Write(inputByteArray, 0, inputByteArray.Length);
        cs.FlushFinalBlock();
        StringBuilder ret = new StringBuilder();
        foreach (byte b in ms.ToArray())
        {
            ret.AppendFormat("{0:X2}", b);
        }
        ret.ToString();
        return ret.ToString();
    }
    private string Decrypt(string pToDecrypt, string sKey)
    {
        DESCryptoServiceProvider des = new DESCryptoServiceProvider();
        byte[] inputByteArray = new byte[pToDecrypt.Length / 2];
        for (int x = 0; x < pToDecrypt.Length / 2; x++)
        {
            int i = (Convert.ToInt32(pToDecrypt.Substring(x * 2, 2), 16));
            inputByteArray[x] = (byte)i;
        }
        des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
        des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
        MemoryStream ms = new MemoryStream();
        CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);
        cs.Write(inputByteArray, 0, inputByteArray.Length);
        cs.FlushFinalBlock();
        StringBuilder ret = new StringBuilder();
        return System.Text.Encoding.Default.GetString(ms.ToArray());
    }
}

        注：這邊在MD5時前后各加了一段字符，這樣增加一點破解難度。

 3.讀寫文件

public class RegistFileHelper
{
    public static string ComputerInfofile = "ComputerInfo.key";
    public static string RegistInfofile = "RegistInfo.key";
    public static void WriteRegistFile(string info)
    {
        WriteFile(info, RegistInfofile);
    }
    public static void WriteComputerInfoFile(string info)
    {
        WriteFile(info, ComputerInfofile);
    }
    public static string ReadRegistFile()
    {
        return ReadFile(RegistInfofile);
    }
    public static string ReadComputerInfoFile()
    {
        return ReadFile(ComputerInfofile);
    }
    public static bool ExistComputerInfofile()
    {
        return File.Exists(ComputerInfofile);
    }
    public static bool ExistRegistInfofile()
    {
        return File.Exists(RegistInfofile);
    }
    private static void WriteFile(string info, string fileName)
    {
        try
        {
            using (StreamWriter sw = new StreamWriter(fileName, false))
            {
                sw.Write(info);
                sw.Close();
            }
        }
        catch (Exception ex)
        {
        }
    }
    private static string ReadFile(string fileName)
    {
        string info = string.Empty;
        try
        {
            using (StreamReader sr = new StreamReader(fileName))
            {
                info = sr.ReadToEnd();
                sr.Close();
            }
        }
        catch (Exception ex)
        {
        }
        return info;
    }
}

4.其他界面代碼：

主界面代碼：

public partial class FormMain : Form
{
    private string encryptComputer = string.Empty;
    private bool isRegist = false;
    private const int timeCount = 30;
    public FormMain()
    {
        InitializeComponent();
        Control.CheckForIllegalCrossThreadCalls = false;
    }
    private void FormMain_Load(object sender, EventArgs e)
    {
        string computer = ComputerInfo.GetComputerInfo();
        encryptComputer = new EncryptionHelper().EncryptString(computer);
        if (CheckRegist() == true)
        {
            lbRegistInfo.Text = "已注冊";
        }
        else
        {
            lbRegistInfo.Text = "待注冊，運行十分鐘后自動關閉";
            RegistFileHelper.WriteComputerInfoFile(encryptComputer);
            TryRunForm();
        }
    }
    /// <summary>
    /// 試運行窗口
    /// </summary>
    private void TryRunForm()
    {
        Thread threadClose = new Thread(CloseForm);
        threadClose.IsBackground = true;
        threadClose.Start();
    }
    private bool CheckRegist()
    {
        EncryptionHelper helper = new EncryptionHelper();
        string md5key = helper.GetMD5String(encryptComputer);
        return CheckRegistData(md5key);
    }
    private bool CheckRegistData(string key)
    {
        if (RegistFileHelper.ExistRegistInfofile() == false)
        {
            isRegist = false;
            return false;
        }
        else
        {
            string info = RegistFileHelper.ReadRegistFile();
            var helper = new EncryptionHelper(EncryptionKeyEnum.KeyB);
            string registData = helper.DecryptString(info);
            if (key == registData)
            {
                isRegist = true;
                return true;
            }
            else
            {
                isRegist = false;
                return false;
            }
        }
    }
    private void CloseForm()
    {
        int count = 0;
        while (count < timeCount && isRegist == false)
        {
            if (isRegist == true)
            {
                return;
            }
            Thread.Sleep(1 * 1000);
            count++;
        }
        if (isRegist == true)
        {
            return;
        }
        else
        {
            this.Close();
        }
    }

    private void btnRegist_Click(object sender, EventArgs e)
    {
        if (lbRegistInfo.Text == "已注冊")
        {
            MessageBox.Show("已經注冊～");
            return;
        }
        string fileName = string.Empty;
        OpenFileDialog openFileDialog = new OpenFileDialog();
        if (openFileDialog.ShowDialog() == DialogResult.OK)
        {
            fileName = openFileDialog.FileName;
        }
        else
        {
            return;
        }
        string localFileName = string.Concat(
            Environment.CurrentDirectory,
            Path.DirectorySeparatorChar,
            RegistFileHelper.RegistInfofile);
        if (fileName != localFileName)
            File.Copy(fileName, localFileName, true);

        if (CheckRegist() == true)
        {
            lbRegistInfo.Text = "已注冊";
            MessageBox.Show("注冊成功～");
        }
    }
}

 注冊機代碼：

public partial class FormMain : Form
{
    public FormMain()
    {
        InitializeComponent();
    }

    private void btnRegist_Click(object sender, EventArgs e)
    {
        string fileName = string.Empty;
        OpenFileDialog openFileDialog = new OpenFileDialog();
        if (openFileDialog.ShowDialog() == DialogResult.OK)
        {
            fileName = openFileDialog.FileName;
        }
        else
        {
            return;
        }
        string localFileName = string.Concat(
            Environment.CurrentDirectory,
            Path.DirectorySeparatorChar,
            RegistFileHelper.ComputerInfofile);

        if (fileName != localFileName)
            File.Copy(fileName, localFileName, true);
        string computer = RegistFileHelper.ReadComputerInfoFile();
        EncryptionHelper help = new EncryptionHelper(EncryptionKeyEnum.KeyB);
        string md5String = help.GetMD5String(computer);
        string registInfo = help.EncryptString(md5String);
        RegistFileHelper.WriteRegistFile(registInfo);
        MessageBox.Show("注冊碼已生成");
    }
}

 最后采用ConfuserEx將可執行文件加密（ ConfuserEx介紹），這樣就不能反編譯獲得源碼。

至此全部完成，只是個人的一些實踐，對自己是一個記錄，同時希望也能對別人有些幫助，如果有什么錯誤，還望不吝指出，共同進步，轉載請保留原文地址。

https://download.csdn.net/download/pfe_nova/7943235

http://www.rzrgm.cn/hanzhaoxin/archive/2013/01/04/2844191.html