File encryption write to document

    /// <summary>    ///file Encryption/// </summary>     Public classFileencryptdecrypt {/// <summary>        ///Encrypted characters/// </summary>         Private Static stringKey ="KANGJINW"; /// <summary>        ///encrypting a key to a file/// </summary>        /// <param name= "sInputFilename" >encryption Key</param>        /// <param name= "sOutputFileName" >Key file path</param>        /// <param name= "SKey" ></param>        Private  Static voidEncryptFile (stringsInputFilename,stringsOutputFileName,stringSKey) {FileStream fsencrypted=NewFileStream (Soutputfilename,filemode.create, FileAccess.Write); DESCryptoServiceProvider DES=NewDESCryptoServiceProvider (); Des. Key=ASCIIEncoding.ASCII.GetBytes (SKey); Des.iv=ASCIIEncoding.ASCII.GetBytes (SKey); ICryptoTransform desencrypt=DES.            CreateEncryptor (); CryptoStream CryptoStream=NewCryptoStream (fsencrypted, desencrypt, CryptoStreamMode.Write); byte[] Fsinput =System.Text.Encoding.Default.GetBytes (sInputFilename); CryptoStream. Write (Fsinput,0, fsinput.length); CryptoStream.            Close ();        Fsencrypted.close (); }        /// <summary>        ///Open key File/// </summary>        /// <param name= "sInputFilename" >Key Path</param>        /// <param name= "SKey" ></param>        Static stringDecryptFile (stringsInputFilename,stringSKey) {DESCryptoServiceProvider DES=NewDESCryptoServiceProvider (); Des. Key=ASCIIEncoding.ASCII.GetBytes (SKey); Des.iv=ASCIIEncoding.ASCII.GetBytes (SKey); FileStream Fsread=NewFileStream (sInputFilename, FileMode.Open, FileAccess.Read); ICryptoTransform Desdecrypt=DES.            CreateDecryptor (); CryptoStream CRYPTOSTREAMDECR=NewCryptoStream (fsread, Desdecrypt, CryptoStreamMode.Read); StreamReader Read=NewStreamReader (CRYPTOSTREAMDECR, System.Text.Encoding.Default); stringReft =read.            ReadToEnd (); Fsread.            Flush (); Fsread.            Close (); returnReft; }        /// <summary>        ///Encrypting Files/// </summary>        /// <param name= "filename" >File storage Path</param>        /// <param name= "Soce" >Encrypt content</param>         Public Static voidEncrypt (stringFileNamestringSoce) {            Try{encryptfile (soce, filename, key); }            Catch(Exception ex) {Throwex; }        }        /// <summary>        ///Decrypt Files/// </summary>        /// <param name= "filename" >Open File path</param>        /// <returns>returns the contents of an encrypted file</returns>         Public Static stringDecrypt (stringfilename) {            Try            {                returndecryptfile (filename, key); }            Catch(Exception ex) {Throwex; }        }    }

File encryption write to document