加密/解密

 

        /// <summary>        /// 加密        /// </summary>        /// <param name="str">加密前字符</param>        /// <returns>加密后密文</returns>        public String JiaMi(String str)        {            String encryptKey = "CSDN";            DESCryptoServiceProvider descsp = new DESCryptoServiceProvider();            byte[] key = Encoding.Unicode.GetBytes(encryptKey);            byte[] data = Encoding.Unicode.GetBytes(str);            System.IO.MemoryStream MStream = new System.IO.MemoryStream();            CryptoStream CStream = new CryptoStream(MStream, descsp.CreateEncryptor(key, key), CryptoStreamMode.Write);            CStream.Write(data, 0, data.Length);            CStream.FlushFinalBlock();            return Convert.ToBase64String(MStream.ToArray());        }        /// <summary>        /// 解密        /// </summary>        /// <param name="str">加密过的密文</param>        /// <returns></returns>        public String JieMi(String str)        {            String encryptKey = "CSDN";            DESCryptoServiceProvider descsp = new DESCryptoServiceProvider();            byte[] key = Encoding.Unicode.GetBytes(encryptKey);            byte[] data = Convert.FromBase64String(str);            System.IO.MemoryStream MStream = new System.IO.MemoryStream();            CryptoStream CStream = new CryptoStream(MStream, descsp.CreateDecryptor(key, key), CryptoStreamMode.Write);            CStream.Write(data, 0, data.Length);            CStream.FlushFinalBlock();            return Encoding.Unicode.GetString(MStream.ToArray());        }