.Net(c#)加密解密之Des

/// <summary>
/// .Net加密解密帮助类
/// </summary>
public class NetCryptoHelper
{
    /// <summary>
    /// Des默认密钥向量
    /// </summary>
    public static byte[] DesIv = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
    /// <summary>
    /// Des加解密钥必须8位
    /// </summary>
    public const string DesKey = "deskey8w";
    /// <summary>
    /// Des加密
    /// </summary>
    /// <param name="source">源字符串</param>
    /// <param name="key">des密钥，长度必须8位</param>
    /// <param name="iv">密钥向量</param>
    /// <returns>加密后的64位字符串</returns>
    public static string EncryptDes(string source, string key, byte[] iv)
    {
        try
        {
            byte[] rgbKeys = Encoding.UTF8.GetBytes(key.Length > 8 ? key.Substring(0, 8) : key);
            byte[] rgbIvs = iv;
            byte[] inputByteArray = Encoding.UTF8.GetBytes(source);
            DESCryptoServiceProvider desProvider = new DESCryptoServiceProvider();
            MemoryStream memoryStream = new MemoryStream();
            CryptoStream cryptoStream = new CryptoStream(memoryStream, desProvider.CreateEncryptor(rgbKeys, rgbIvs), CryptoStreamMode.Write);
            cryptoStream.Write(inputByteArray, 0, inputByteArray.Length);
            cryptoStream.FlushFinalBlock();
            // 1.第一种
            return Convert.ToBase64String(memoryStream.ToArray());

            // 2.第二种
            //StringBuilder result = new StringBuilder();
            //foreach (byte b in memoryStream.ToArray())
            //{
            //    result.AppendFormat("{0:X2}", b);
            //}
            //return result.ToString();
        }
        catch
        {
            return source;
        }
    }
    /// <summary>
    /// Des解密
    /// </summary>
    /// <param name="source">源字符串</param>
    /// <param name="key">des密钥，长度必须8位</param>
    /// <param name="iv">密钥向量</param>
    /// <returns>解密后的字符串</returns>
    public static string DecryptDes(string source, string key, byte[] iv)
    {
        try
        {
            byte[] rgbKeys = Encoding.UTF8.GetBytes(key.Length > 8 ? key.Substring(0, 8) : key);
            byte[] rgbIvs = iv;
            byte[] inputByteArray = Convert.FromBase64String(source);
            DESCryptoServiceProvider desProvider = new DESCryptoServiceProvider();
            MemoryStream memoryStream = new MemoryStream();
            CryptoStream cryptoStream = new CryptoStream(memoryStream, desProvider.CreateDecryptor(rgbKeys, rgbIvs), CryptoStreamMode.Write);
            cryptoStream.Write(inputByteArray, 0, inputByteArray.Length);
            cryptoStream.FlushFinalBlock();
            return Encoding.UTF8.GetString(memoryStream.ToArray());
        }
        catch
        {
            return source;
        }
    }
}

class Program
{
    static void Main(string[] args)
    {
        string plainText = "博客园",
            encryptString = NetCryptoHelper.EncryptDes(plainText, NetCryptoHelper.DesKey, NetCryptoHelper.DesIv);
        Console.WriteLine("加密前的字符串:{0}", plainText);
        Console.WriteLine("加密后的字符串:{0}", encryptString);
        Console.WriteLine("解密后的字符串:{0}", NetCryptoHelper.DecryptDes(encryptString, NetCryptoHelper.DesKey, NetCryptoHelper.DesIv));
        Console.ReadKey();
    }
}