C# 生成注册码的代码一例

string t = DateTime.Now.Ticks.ToString();

t = DESKey.DESEncrypt(t, DESKey.DesKeyStr);
string[] strid = new string[t.Length];//
for (int i = 0; i < t.Length; i++)//把字符赋给数组
{
strid[i] = t.Substring(i, 1);
}
string s = "";
Random rdid = new Random();
for (int i = 0; i < 9; i++)//从数组随机抽取字符组成新的字符生成机器三
{
s += strid[rdid.Next(0, strid.Length)];
}

class DESKey
{
public const string DesKeyStr = "BLUE2013";

#region DES加密
/// <summary>
/// DES加密
/// </summary>
/// <param name="pToEncrypt">需要加密的字符串</param>
/// <returns>加密后的字符串</returns>
public static string DESEncrypt(string pToEncrypt, string DesKeyStr)
{
try
{
DESCryptoServiceProvider des = new DESCryptoServiceProvider();
byte[] inputByteArray = Encoding.Default.GetBytes(pToEncrypt);
des.Key = ASCIIEncoding.ASCII.GetBytes(DesKeyStr);
des.IV = ASCIIEncoding.ASCII.GetBytes(DesKeyStr);
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();
}
catch
{

return "";
}
}
#endregion

#region DES解密
/// <summary>
/// DES解密
/// </summary>
/// <param name="pToDecrypt">加密后的字符串</param>
/// <returns>解密后的字符串</returns>
public static string DESDecrypt(string pToDecrypt, string DesKeyStr)
{
try
{
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(DesKeyStr);
des.IV = ASCIIEncoding.ASCII.GetBytes(DesKeyStr);
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());
}
catch
{

return "";
}
}
#endregion
}