/// <summary>
/// 加密
/// </summary>
/// <param name="decryptString">要被加密数据</param>
/// <param name="decryptKey">DES算法的工作密钥</param>
/// <returns>密文</returns>
public static string Encrypt(string encryptString, string encryptKey)
{
encryptKey = UniversalTool.GetSubString(encryptKey, 8, "");
encryptKey = encryptKey.PadRight(8, ' ');
byte[] bytes = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8));
byte[] keys = Keys;
byte[] buffer = Encoding.UTF8.GetBytes(encryptString);
DESCryptoServiceProvider provider = new DESCryptoServiceProvider();
MemoryStream stream = new MemoryStream();
CryptoStream stream2 = new CryptoStream(stream, provider.CreateEncryptor(bytes, keys), CryptoStreamMode.Write);
stream2.Write(buffer, 0, buffer.Length);
stream2.FlushFinalBlock();
return(Convert.ToBase64String(stream.ToArray()));//Base64是网络上最常见的用于传输8Bit字节代码的编码方式之一,Base64要求把每三个8Bit的字节转换为四个6Bit的字节（3*8 = 4*6 = 24），然后把6Bit再添两位高位0，组成四个8Bit的字节。
//Base64编码可用于在HTTP环境下传递较长的标识信息,如较长的唯一标识符（一般为128-bit的UUID）编码为一个字符串，用作HTTP表单和HTTP GET URL中的参数，或者将二进制数据编码为适合放在URL（包括隐藏表单域）中的形式。此时，采用Base64编码不仅比较简短，同时也具有不可读性，即所编码的数据不会被人用肉眼所直接看到。
}
private static byte[] Keys = new byte[] { 0x12, 0x34, 0x56, 120, 0x90, 0xab, 0xcd, 0xef };//8个bit位，是DES算法的初始化向量 加解密钥也是8位;
/// <summary>
/// 解密字符串
/// </summary>
/// <param name="decryptString">是要被解密的密文数据</param>
/// <param name="decryptKey">DES算法的工作密钥</param>
/// <returns>明文</returns>
public static string Decrypt(string decryptString, string decryptKey)
{
try
{
decryptKey = UniversalTool.GetSubString(decryptKey, 8, "");
decryptKey = decryptKey.PadRight(8, ' ');
byte[] bytes = Encoding.UTF8.GetBytes(decryptKey);
byte[] keys = Keys;
byte[] buffer = Convert.FromBase64String(decryptString);
DESCryptoServiceProvider provider = new DESCryptoServiceProvider();
MemoryStream stream = new MemoryStream();
CryptoStream stream2 = new CryptoStream(stream, provider.CreateDecryptor(bytes, keys), CryptoStreamMode.Write);
stream2.Write(buffer, 0, buffer.Length);
stream2.FlushFinalBlock();
return(Encoding.UTF8.GetString(stream.ToArray()));
}
catch
{
return("");
}
}