public class DESCrypto    {        /// <summary>        /// 初始化des实例秘钥及向量        /// </summary>        /// <param name="key"></param>        /// <returns></returns>        private static DESCryptoServiceProvider InitDESInstance(string key)        {            DESCryptoServiceProvider des = new DESCryptoServiceProvider();            byte[] salt = new byte[] { 0x0A, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0xF1 };            byte[] keyByte = Encoding.UTF8.GetBytes(key);            Rfc2898DeriveBytes rfcKey = new Rfc2898DeriveBytes(keyByte, salt, 8);            Rfc2898DeriveBytes rfcIv = new Rfc2898DeriveBytes("0987654321", salt, 8);            des.Key = rfcKey.GetBytes(8);            des.IV = rfcIv.GetBytes(8);            return des;        }        #region 基于Base64的加密解密（不其他格式的加解密方法配合使用）        /// <summary>        /// 基于Base64        /// </summary>        /// <param name="plaintext"></param>        /// <param name="key"></param>        /// <returns></returns>        public static string DESEncryptBase64(string plaintext,string key)        {            DESCryptoServiceProvider des = InitDESInstance(key);            byte[] dataByteArray = Encoding.UTF8.GetBytes(plaintext);            string ciphertext = "";            using (MemoryStream ms = new MemoryStream())            using (CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write))            {                cs.Write(dataByteArray, 0, dataByteArray.Length);                cs.FlushFinalBlock();                ciphertext = Convert.ToBase64String(ms.ToArray());            }            return ciphertext;        }        /// <summary>        /// 基于Base64        /// </summary>        /// <param name="encrypt"></param>        /// <param name="key"></param>        /// <returns></returns>        public static string DESDecryptBase64(string encrypt, string key)        {            DESCryptoServiceProvider des = InitDESInstance(key);            byte[] dataByteArray = Convert.FromBase64String(encrypt);            using (MemoryStream ms = new MemoryStream())            using (CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write))            {                cs.Write(dataByteArray, 0, dataByteArray.Length);                cs.FlushFinalBlock();                return Encoding.UTF8.GetString(ms.ToArray());            }        }        #endregion        #region 基于2位十六进制格式的加密解密（不其他格式的加解密方法配合使用）        /// <summary>        /// 加密        /// </summary>        /// <param name="plaintext">明文</param>        /// <param name="key"></param>        /// <returns></returns>        public static string DESEncrypt(string plaintext, string key)        {            DESCryptoServiceProvider des = InitDESInstance(key);            StringBuilder sb = new StringBuilder();            byte[] dataByteArray = Encoding.UTF8.GetBytes(plaintext);            string ciphertext = "";            using (MemoryStream ms = new MemoryStream())            using (CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write))            {                cs.Write(dataByteArray, 0, dataByteArray.Length);                cs.FlushFinalBlock();                //输出加密文本                foreach (byte b in ms.ToArray())                {                    sb.AppendFormat("{0:X2}", b);                }                ciphertext = sb.ToString();            }            return ciphertext;        }        /// <summary>        /// 解密        /// </summary>        /// <param name="ciphertext">密文</param>        /// <param name="key"></param>        /// <returns></returns>        public static string DESDecrypt(string ciphertext, string key)        {            DESCryptoServiceProvider des = InitDESInstance(key);            byte[] dataByteArray = new byte[ciphertext.Length / 2];            for (int x = 0; x < ciphertext.Length / 2; x++)            {                int i = (Convert.ToInt32(ciphertext.Substring(x * 2, 2), 16));                dataByteArray[x] = (byte)i;            }            using (MemoryStream ms = new MemoryStream())            using (CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write))            {                cs.Write(dataByteArray, 0, dataByteArray.Length);                cs.FlushFinalBlock();                return Encoding.UTF8.GetString(ms.ToArray());            }        }        #endregion        #region 文件加密解密（不其他格式的加解密方法配合使用）        /// <summary>        /// 加密文件        /// </summary>        /// <param name="sourceFile">文件的物理路径</param>        /// <param name="encryptFile">文件的物理路径</param>        /// <param name="key"></param>        public static void DESEncryptFile(string sourceFile, string encryptFile, string key)        {            if (string.IsNullOrEmpty(sourceFile) || string.IsNullOrEmpty(encryptFile)||!File.Exists(sourceFile)) return;                        DESCryptoServiceProvider des = InitDESInstance(key);            using (FileStream sourceStream = new FileStream(sourceFile, FileMode.Open, FileAccess.Read))            using (FileStream encryptStream = new FileStream(encryptFile, FileMode.Create, FileAccess.Write))            {                byte[] dataByteArray = new byte[sourceStream.Length];                sourceStream.Read(dataByteArray, 0, dataByteArray.Length);                using (CryptoStream cs = new CryptoStream(encryptStream, des.CreateEncryptor(), CryptoStreamMode.Write))                {                    cs.Write(dataByteArray, 0, dataByteArray.Length);                    cs.FlushFinalBlock();                }            }        }        /// <summary>        /// 解密文件        /// </summary>        /// <param name="encryptFile">文件的物理路径</param>        /// <param name="decryptFile">文件的物理路径</param>        /// <param name="key"></param>        public static void DESDecryptFile(string encryptFile, string decryptFile, string key)        {            if (string.IsNullOrEmpty(encryptFile) || string.IsNullOrEmpty(decryptFile) || !File.Exists(encryptFile))return;            DESCryptoServiceProvider des = InitDESInstance(key);            using (FileStream encryptStream = new FileStream(encryptFile, FileMode.Open, FileAccess.Read))            using (FileStream decryptStream = new FileStream(decryptFile, FileMode.Create, FileAccess.Write))            {                byte[] dataByteArray = new byte[encryptStream.Length];                encryptStream.Read(dataByteArray, 0, dataByteArray.Length);                using (CryptoStream cs = new CryptoStream(decryptStream, des.CreateDecryptor(), CryptoStreamMode.Write))                {                    cs.Write(dataByteArray, 0, dataByteArray.Length);                    cs.FlushFinalBlock();                }            }        }        /// <summary>        /// 加密文本并输出到文件        /// </summary>        /// <param name="plaintext"></param>        /// <param name="FileName">文件的物理路径</param>        /// <param name="Key"></param>        public static void DESEncryptTextToFile(string plaintext, string FileName, string key)        {            if (string.IsNullOrEmpty(FileName)) return;            DESCryptoServiceProvider des = InitDESInstance(key);            byte[] dataByteArray = Encoding.UTF8.GetBytes(plaintext);            using (FileStream fStream = File.Open(FileName, FileMode.Create))            using (CryptoStream cStream = new CryptoStream(fStream, des.CreateEncryptor(), CryptoStreamMode.Write))            {                cStream.Write(dataByteArray, 0, dataByteArray.Length);                cStream.FlushFinalBlock();            }        }        /// <summary>        /// 解密文件中的密文并返回        /// </summary>        /// <param name="FileName"></param>        /// <param name="Key"></param>        /// <returns></returns>        public static string DESDecryptTextFromFile(string FileName, string key)        {            if (string.IsNullOrEmpty(FileName)||!File.Exists(FileName)) return "";            DESCryptoServiceProvider des = InitDESInstance(key);            using (FileStream fStream = File.Open(FileName, FileMode.OpenOrCreate))            using (CryptoStream cStream = new CryptoStream(fStream, des.CreateDecryptor(), CryptoStreamMode.Read))            using (StreamReader sReader = new StreamReader(cStream))            {                string val = sReader.ReadToEnd();                return val;            }        }        #endregion    }