c# My encrypt and decrypt function is not working some time

[Mou_inn]

when i am passing normal alphabet to my encrypt and decrypt function then it is working as expected but when i am passing alphanumeric text to encrypt and decrypt function then it is not working.

say when i pass encrypt("test1") or decrypt("test1") then it is not working. specially decrypt not working with alphanumeric case.

i want to restructure my encrypt and decrypt function as a result whatever value i pass the function can work. suppose i may pass alpha numeric data with special character. so plerase see the code and come with rectified version.

a small wrapper around encrypt/decrypt

private string encrypt(string message)
{
EncryptClass.EncryptClass ec = new EncryptClass.EncryptClass();
string encryStr = ec.custEncrypt(message);
return encryStr;
}

private string decrypt(string message)
{
EncryptClass.EncryptClass ec = new EncryptClass.EncryptClass();
string decryptStr = message;
return ec.custDecrypt(decryptStr);
}

full code for encrypt ans decrypt

public class EncryptClass
{
DESCryptoServiceProvider rj;
byte[] key = new byte[] { 11, 9, 3, 4, 1, 8, 12, 7 };
byte[] IV = new byte[] { 1, 8, 7, 16, 1, 9, 0, 3 };
public EncryptClass()
{
//
// TODO: Add constructor logic here
//
rj = new DESCryptoServiceProvider();
}

// for encryption
public string custEncrypt(string message)
{
//create a memory stream
MemoryStream ciphertextmem = new MemoryStream();
//create a crypto stream in write mode
CryptoStream crystm = new CryptoStream(ciphertextmem, rj.CreateEncryptor(key, IV), CryptoStreamMode.Write);
//Encode the passed plain text string into Unicode byte stream
Byte[] plaintextbyte = new UnicodeEncoding().GetBytes(message);
//Write the plaintext byte stream to CryptoStream
crystm.Write(plaintextbyte, 0, plaintextbyte.Length);
//dont forget to close the stream
crystm.Close();
//Extract the ciphertext byte stream and close the MemoryStream
Byte[] ciphertextbyte = ciphertextmem.ToArray();
ciphertextmem.Close();
//Encode the ciphertext byte into Unicode string
string ciphertext = new UnicodeEncoding().GetString(ciphertextbyte);
return ciphertext;
//return "encry " + message;


}

// for decryption
public string custDecrypt(string message)
{
//Create a memory stream from which CryptoStream will read the cipher text
MemoryStream ciphertextmem = new MemoryStream(new UnicodeEncoding().GetBytes(message));

//Create a CryptoStream in Read Mode; initialise with the Rijndaels Decryptor ICryptoTransform
CryptoStream crystm = new CryptoStream(ciphertextmem, rj.CreateDecryptor(key, IV), CryptoStreamMode.Read);

//Create a temporary memory stream to which we will copy the
//plaintext byte array from CryptoStream

MemoryStream plaintextmem = new MemoryStream();
do
{
//Create a byte array into which we will read the plaintext
//from CryptoStream
Byte[] buf = new Byte[100];

//read the plaintext from CryptoStream
int actualbytesread = crystm.Read(buf, 0, 100);

//if we have reached the end of stream quit the loop
if (0 == actualbytesread)
break;

//copy the plaintext byte array to MemoryStream
plaintextmem.Write(buf, 0, actualbytesread);

} while (true);

//dont forget to close the streams
crystm.Close();
ciphertextmem.Close();

//Extract the plaintext byte stream and close the MemoryStream
Byte[] plaintextbyte = plaintextmem.ToArray();
plaintextmem.Close();

//Encode the plaintext byte into Unicode string
string plaintext = new UnicodeEncoding().GetString(plaintextbyte);

return plaintext;

//return "decry "+ message;
}
}

please see my code and rectified area as a result it should work if i pass only text or if i pass text with numeric data or alphanumeric with special character.

looking for help.

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