C # CryptoStream

usingSystem;usingSystem.IO;usingSystem.Security.Cryptography;namespacerijndaelmanaged_example{classRijndaelexample { Public Static voidMain () {Try            {                stringOriginal ="Here's some data to encrypt!"; //Create A new instance of the Rijndael//class. This generates a new key and initialization//vector (IV).                using(Rijndael Myrijndael =rijndael.create ()) {                    //Encrypt The string to an array of bytes.                    byte[] encrypted =encryptstringtobytes (Original, Myrijndael.key, MYRIJNDAEL.IV); //Decrypt the bytes to a string.                    stringroundtrip =decryptstringfrombytes (Encrypted, Myrijndael.key, MYRIJNDAEL.IV); //Display The original data and the decrypted data.Console.WriteLine ("Original: {0}", original); Console.WriteLine ("Round trip: {0}", roundtrip); }            }            Catch(Exception e) {Console.WriteLine ("Error: {0}", E.message); }        }        Static byte[] Encryptstringtobytes (stringPlainText,byte[] Key,byte[] IV) {//Check arguments.            if(PlainText = =NULL|| Plaintext.length <=0)                Throw NewArgumentNullException ("plaintext"); if(Key = =NULL|| Key.length <=0)                Throw NewArgumentNullException ("Key"); if(IV = =NULL|| Iv.. Length <=0)                Throw NewArgumentNullException ("Key"); byte[] encrypted; //Create an Rijndael object//With the specified key and Iv.            using(Rijndael Rijalg =rijndael.create ()) {Rijalg.key=Key; Rijalg.iv=IV; //Create a decrytor to perform the stream transform.ICryptoTransform encryptor =Rijalg.createencryptor (Rijalg.key, RIJALG.IV); //Create The streams used for encryption.                using(MemoryStream msencrypt =NewMemoryStream ()) {                    using(CryptoStream csencrypt =NewCryptoStream (Msencrypt, Encryptor, CryptoStreamMode.Write)) {                        using(StreamWriter Swencrypt =NewStreamWriter (Csencrypt)) {                            //Write all data to the stream.Swencrypt.write (plaintext); } Encrypted=Msencrypt.toarray (); }                }            }            //Return the encrypted bytes from the memory stream.            returnencrypted; }        Static stringDecryptstringfrombytes (byte[] Ciphertext,byte[] Key,byte[] IV) {//Check arguments.            if(Ciphertext = =NULL|| Ciphertext.length <=0)                Throw NewArgumentNullException ("Ciphertext"); if(Key = =NULL|| Key.length <=0)                Throw NewArgumentNullException ("Key"); if(IV = =NULL|| Iv.. Length <=0)                Throw NewArgumentNullException ("Key"); //Declare The string used to hold//The decrypted text.            stringplaintext =NULL; //Create an Rijndael object//With the specified key and Iv.            using(Rijndael Rijalg =rijndael.create ()) {Rijalg.key=Key; Rijalg.iv=IV; //Create a decrytor to perform the stream transform.ICryptoTransform decryptor =Rijalg.createdecryptor (Rijalg.key, RIJALG.IV); //Create The streams used for decryption.                using(MemoryStream msdecrypt =NewMemoryStream (ciphertext)) {                    using(CryptoStream csdecrypt =NewCryptoStream (Msdecrypt, Decryptor, CryptoStreamMode.Read)) {                        using(StreamReader Srdecrypt =NewStreamReader (Csdecrypt)) {                            //Read The decrypted bytes from the decrypting stream//and place them in a string.plaintext =Srdecrypt.readtoend (); }                    }                }            }            returnplaintext; }    }}

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C # CryptoStream