加解密2-字符串

加密字符串：

        /// <summary>
        /// DES加密字符串
        /// 加密密钥,要求为8位
        /// 加密成功返回加密后的字符串，失败返回源串
        /// </summary>
        /// <param name="encryptString">待加密的字符串</param>
        /// <param name="decryptIV">加密因子</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, string encryptIV, string encryptKey) 
        {
            try
            {
                byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8));
                byte[] rgbIV = Encoding.UTF8.GetBytes(encryptIV.Substring(0, 8));
                byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);
                DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider();

                MemoryStream mStream = new MemoryStream();
                //加密方式写入到mSteram
                CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
                cStream.Write(inputByteArray, 0, inputByteArray.Length);
                cStream.FlushFinalBlock();
                return Convert.ToBase64String(mStream.ToArray());
            }
            catch
            {
                return encryptString;//异常返回原始字符串 
            }
        }

解密字符串：

         /// <summary>
        /// DES解密字符串
        /// 解密密钥,要求为8位,和加密密钥相同
        /// 解密成功返回解密后的字符串，失败返源串
        /// </summary>
        /// <param name="decryptString">待解密的字符串</param>
        /// <param name="decryptIV">解密因子</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</
        public static string DecryptDES(string decryptString,string decryptIV,string decryptKey) 
        {
            try
            {
                byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey.Substring(0, 8));
                byte[] rgbIV = Encoding.UTF8.GetBytes(decryptIV.Substring(0, 8));
                byte[] inputByteArray = Convert.FromBase64String(decryptString);
               
                //算法
                DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider();
               
               //基础流
                MemoryStream mStream = new MemoryStream();
                
                //以解密方式写入mStream
                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;//异常返回原始字符串         
            }
        }