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Rijndael Class
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Rijndael Class

Represents the base class from which all implementations of the Rijndael symmetric encryption algorithm must inherit.

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

'Declaration
<ComVisibleAttribute(True)> _
Public MustInherit Class Rijndael
	Inherits SymmetricAlgorithm
'Usage
Dim instance As Rijndael

/** @attribute ComVisibleAttribute(true) */ 
public abstract class Rijndael extends SymmetricAlgorithm
ComVisibleAttribute(true) 
public abstract class Rijndael extends SymmetricAlgorithm
Not applicable.

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

The following code example uses the Rijndael class to encrypt and then decrypt data.

Imports System.Security.Cryptography
Imports System.Text
Imports System.IO

Module RijndaelSample

    Sub Main()
        Try
            ' Create a new Rijndael object to generate a key
            ' and initialization vector (IV).
            Dim RijndaelAlg As Rijndael = Rijndael.Create

            ' Create a string to encrypt.
            Dim sData As String = "Here is some data to encrypt."
            Dim FileName As String = "CText.txt"

            ' Encrypt text to a file using the file name, key, and IV.
            EncryptTextToFile(sData, FileName, RijndaelAlg.Key, RijndaelAlg.IV)

            ' Decrypt the text from a file using the file name, key, and IV.
            Dim Final As String = DecryptTextFromFile(FileName, RijndaelAlg.Key, RijndaelAlg.IV)

            ' Display the decrypted string to the console.
            Console.WriteLine(Final)
        Catch e As Exception
            Console.WriteLine(e.Message)
        End Try

        Console.ReadLine()

    End Sub


    Sub EncryptTextToFile(ByVal Data As String, ByVal FileName As String, ByVal Key() As Byte, ByVal IV() As Byte)
        Try
            ' Create or open the specified file.
            Dim fStream As FileStream = File.Open(FileName, FileMode.OpenOrCreate)

            ' Create a new Rijndael object.
            Dim RijndaelAlg As Rijndael = Rijndael.Create

            ' Create a CryptoStream using the FileStream 
            ' and the passed key and initialization vector (IV).
            Dim cStream As New CryptoStream(fStream, _
                                           RijndaelAlg.CreateEncryptor(Key, IV), _
                                           CryptoStreamMode.Write)

            ' Create a StreamWriter using the CryptoStream.
            Dim sWriter As New StreamWriter(cStream)

            Try

                ' Write the data to the stream 
                ' to encrypt it.
                sWriter.WriteLine(Data)
            Catch e As Exception

                Console.WriteLine("An error occurred: {0}", e.Message)

            Finally

                ' Close the streams and
                ' close the file.
                sWriter.Close()
                cStream.Close()
                fStream.Close()

            End Try
        Catch e As CryptographicException
            Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
        Catch e As UnauthorizedAccessException
            Console.WriteLine("A file error occurred: {0}", e.Message)
        End Try
    End Sub


    Function DecryptTextFromFile(ByVal FileName As String, ByVal Key() As Byte, ByVal IV() As Byte) As String
        Try
            ' Create or open the specified file. 
            Dim fStream As FileStream = File.Open(FileName, FileMode.OpenOrCreate)

            ' Create a new Rijndael object.
            Dim RijndaelAlg As Rijndael = Rijndael.Create

            ' Create a CryptoStream using the FileStream 
            ' and the passed key and initialization vector (IV).
            Dim cStream As New CryptoStream(fStream, _
                                            RijndaelAlg.CreateDecryptor(Key, IV), _
                                            CryptoStreamMode.Read)

            ' Create a StreamReader using the CryptoStream.
            Dim sReader As New StreamReader(cStream)

            ' Read the data from the stream 
            ' to decrypt it.
            Dim val As String = Nothing

            Try

                val = sReader.ReadLine()

            Catch e As Exception
                Console.WriteLine("An Cerror occurred: {0}", e.Message)
            Finally
                ' Close the streams and
                ' close the file.
                sReader.Close()
                cStream.Close()
                fStream.Close()


            End Try

            ' Return the string. 
            Return val

        Catch e As CryptographicException
            Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
            Return Nothing
        Catch e As UnauthorizedAccessException
            Console.WriteLine("A file error occurred: {0}", e.Message)
            Return Nothing
        End Try
    End Function
End Module

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

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0

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