C# DES 加密 解密

 //注意:密钥必须为８位
        private const string m_strEncryptKey = "abcd1234";
        /// <summary>
        /// 加密字符串
        /// </summary>
        /// <param name="p_strInput">明码</param>
        /// <returns>加密后的密码</returns>
        public static string DesEncrypt(string p_strInput)
        {
            byte[] byKey = null;
            byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
            try
            {
                byKey = System.Text.Encoding.UTF8.GetBytes(m_strEncryptKey.Substring(0, 8));
                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                byte[] inputByteArray = Encoding.UTF8.GetBytes(p_strInput);
                MemoryStream ms = new MemoryStream();
                CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(byKey, IV), CryptoStreamMode.Write);
                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();
                return Convert.ToBase64String(ms.ToArray());
            }
            catch (System.Exception ex)
            {
                throw (ex);
            }
        }

        /// <summary>
        /// 解密字符串
        /// </summary>
        /// <param name="p_strInput">加了密的字符串</param>
        public static string DesDecrypt(string p_strInput)
        {
            byte[] byKey = null;
            byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
            byte[] inputByteArray = new Byte[p_strInput.Length];

            try
            {
                byKey = System.Text.Encoding.UTF8.GetBytes(m_strEncryptKey.Substring(0, 8));
                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                inputByteArray = Convert.FromBase64String(p_strInput);
                MemoryStream ms = new MemoryStream();
                CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(byKey, IV), CryptoStreamMode.Write);
                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();
                System.Text.Encoding encoding = new System.Text.UTF8Encoding();
                return encoding.GetString(ms.ToArray());
            }
            catch (System.Exception ex)
            {
                throw (ex);
            }
        }