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RijndaelManaged Class
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RijndaelManaged Class

Accesses the managed version of the Rijndael algorithm. This class cannot be inherited.

Namespace:  System.Security.Cryptography
Assembly:  mscorlib (in mscorlib.dll)

[ComVisibleAttribute(true)]
public ref class RijndaelManaged sealed : public Rijndael

This algorithm supports key lengths of 128, 192, or 256 bits.

The following example demonstrates how to encrypt and decrypt sample data using the RijndaelManaged class.

#using <System.dll>

using namespace System;
using namespace System::IO;
using namespace System::Security::Cryptography;


class RijndaelMemoryExample
{
 public:
    static array<Byte>^ encryptStringToBytes_AES(String^ plainText, array<Byte>^ Key, array<Byte>^ IV)
    {
        // Check arguments. 
        if (!plainText || plainText->Length <= 0)
            throw gcnew ArgumentNullException("plainText");
        if (!Key || Key->Length <= 0)
            throw gcnew ArgumentNullException("Key");
        if (!IV  || IV->Length <= 0)
            throw gcnew ArgumentNullException("IV");

        // Declare the streams used 
        // to encrypt to an in memory 
        // array of bytes.
		MemoryStream^   msEncrypt;
        CryptoStream^   csEncrypt;
        StreamWriter^   swEncrypt;

        // Declare the RijndaelManaged object 
        // used to encrypt the data.
        RijndaelManaged ^ aesAlg;

        try
        {
            // Create a RijndaelManaged object 
            // with the specified key and IV.
            aesAlg = gcnew RijndaelManaged();
			aesAlg->Padding = PaddingMode::PKCS7;
            aesAlg->Key = Key;
            aesAlg->IV = IV;

            // Create an encryptor to perform the stream transform.
            ICryptoTransform ^ encryptor = aesAlg->CreateEncryptor(aesAlg->Key, aesAlg->IV);

            // Create the streams used for encryption.
            msEncrypt = gcnew MemoryStream();
			csEncrypt = gcnew CryptoStream(msEncrypt, encryptor, CryptoStreamMode::Write);
            swEncrypt = gcnew StreamWriter(csEncrypt);

            //Write all data to the stream.
            swEncrypt->Write(plainText);
			swEncrypt->Flush();
			csEncrypt->FlushFinalBlock();
			msEncrypt->Flush();
        }
        finally
        {
            // Clean things up. 

            // Close the streams. 
            if(swEncrypt)
                swEncrypt->Close();
            if (csEncrypt)
                csEncrypt->Close();

            // Clear the RijndaelManaged object. 
            if (aesAlg)
                aesAlg->Clear();
        }

        // Return the encrypted bytes from the memory stream. 
        return msEncrypt->ToArray();
    }

    static String ^ decryptStringFromBytes_AES(array<Byte>^ cipherText, array<Byte>^ Key, array<Byte>^ IV)
    {
        // Check arguments. 
        if (!cipherText || cipherText->Length <= 0)
            throw gcnew ArgumentNullException("cipherText");
        if (!Key || Key->Length <= 0)
            throw gcnew ArgumentNullException("Key");
        if (!IV || IV->Length <= 0)
            throw gcnew ArgumentNullException("IV");

        // TDeclare the streams used 
        // to decrypt to an in memory 
        // array of bytes.
        MemoryStream^ msDecrypt;
        CryptoStream^ csDecrypt;
        StreamReader^ srDecrypt;

        // Declare the RijndaelManaged object 
        // used to decrypt the data.
        RijndaelManaged^ aesAlg;

        // Declare the string used to hold 
        // the decrypted text.
        String^ plaintext;

        try
        {
            // Create a RijndaelManaged object 
            // with the specified key and IV.
            aesAlg = gcnew RijndaelManaged();
			aesAlg->Padding = PaddingMode::PKCS7;
            aesAlg->Key = Key;
            aesAlg->IV = IV;

            // Create a decrytor to perform the stream transform.
			ICryptoTransform ^ decryptor = aesAlg->CreateDecryptor(aesAlg->Key, aesAlg->IV);

            // Create the streams used for decryption.
            msDecrypt = gcnew MemoryStream(cipherText);
			csDecrypt = gcnew CryptoStream(msDecrypt, decryptor, CryptoStreamMode::Read);
            srDecrypt = gcnew StreamReader(csDecrypt);

            // Read the decrypted bytes from the decrypting stream 
            // and place them in a string.
            plaintext = srDecrypt->ReadToEnd();
        }
        finally
        {
            // Clean things up. 

            // Close the streams. 
            if (srDecrypt)
                srDecrypt->Close();
            if (csDecrypt)
                csDecrypt->Close();
            if (msDecrypt)
                msDecrypt->Close();

            // Clear the RijndaelManaged object. 
            if (aesAlg)
                aesAlg->Clear();
        }

        return plaintext;
    }
};

int main()
{
    try
    {
        String^ original = "Here is some data to encrypt!";

        // Create a new instance of the RijndaelManaged 
        // class.  This generates a new key and initialization 
        // vector (IV).
        RijndaelManaged^ myRijndael = gcnew RijndaelManaged();

        // Encrypt the string to an array of bytes. 
		array<Byte>^ encrypted = RijndaelMemoryExample::encryptStringToBytes_AES(original, myRijndael->Key, myRijndael->IV);

        // Decrypt the bytes to a string.
        String^ roundtrip = RijndaelMemoryExample::decryptStringFromBytes_AES(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);
    }

	return 0;
}

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0

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