DES加密&解密字符串

using System.Security.Cryptography;
using System.IO;
using System.Text;

    //默认密钥向量
    private static byte[] DyncKeys = { 0x12, 0x14, 0x14, 0x15, 0xA0, 0xA1, 0xB0, 0xB1 };
    //默认加密密钥
    private static byte[] Key = { 0x01, 0x02, 0x03, 0x04, 0xA0, 0xAB, 0xAC, 0xAD };

    /// <summary>
    /// DES加密字符串/// </summary>
    /// <param name="encryptString">待加密的字符串</param>
    /// <param name="encryptKey">加密密钥,要求为8位</param>
    /// <returns>加密成功返回加密后的字符串，失败返回源串</returns>
    public static string EncryptDES(string encryptString, byte[] encryptKey)
    {
        try
        {
            byte[] rgbKey = encryptKey;
            byte[] rgbIV = DyncKeys;
            byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);
            DESCryptoServiceProvider dCSP = new DESCryptoServiceProvider();
            MemoryStream mStream = new MemoryStream();
            CryptoStream cStream = new CryptoStream(mStream, dCSP.CreateEncryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
            cStream.Write(inputByteArray, 0, inputByteArray.Length);
            cStream.FlushFinalBlock();
            return Convert.ToBase64String(mStream.ToArray());
        }
        catch
        {
            return encryptString;
        }
    }

    /// <summary>
    /// DES解密字符串/// </summary>
    /// <param name="decryptString">待解密的字符串</param>
    /// <param name="decryptKey">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，失败返源串</returns>
    public static string DecryptDES(string decryptString, byte[] decryptKey)
    {
        try
        {
            byte[] rgbKey = decryptKey;
            byte[] rgbIV = DyncKeys;
            byte[] inputByteArray = Convert.FromBase64String(decryptString);
            DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider();
            MemoryStream mStream = new MemoryStream();
            CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
            cStream.Write(inputByteArray, 0, inputByteArray.Length);
            cStream.FlushFinalBlock();
            return Encoding.UTF8.GetString(mStream.ToArray());
        }
        catch
        {
            return decryptString;
        }
    }