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SymmetricAlgorithm.Create Method

Creates an instance of the default implementation of a symmetric algorithm.

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

'Declaration
Public Shared Function Create As SymmetricAlgorithm

Return Value

Type: System.Security.Cryptography.SymmetricAlgorithm
A new RijndaelManaged instance, unless the default settings have been changed using the <cryptoClass> Element.

By default, this overload uses the RijndaelManaged implementation of a symmetric algorithm. If you want to specify a different implementation, use the Create overload, which lets you specify an algorithm name, instead.

The following example uses the RijndaelManaged class with the specified Key property and initialization vector (IV) to encrypt a file specified by inName, and outputs the encrypted result to the file specified by outName. The desKey and desIV parameters to the method are 8-byte arrays. You must have the high encryption pack installed to run this example.


    Private Shared Sub EncryptData(inName As String, outName As String, _
    rijnKey() As Byte, rijnIV() As Byte)

        'Create the file streams to handle the input and output files.
        Dim fin As New FileStream(inName, FileMode.Open, FileAccess.Read)
        Dim fout As New FileStream(outName, FileMode.OpenOrCreate, _
           FileAccess.Write)
        fout.SetLength(0)

        'Create variables to help with read and write.
        Dim bin(100) As Byte 'This is intermediate storage for the encryption.
        Dim rdlen As Long = 0 'This is the total number of bytes written.
        Dim totlen As Long = fin.Length 'Total length of the input file.
        Dim len As Integer 'This is the number of bytes to be written at a time.
        'Creates the default implementation, which is RijndaelManaged.
        Dim rijn As SymmetricAlgorithm = SymmetricAlgorithm.Create()
        Dim encStream As New CryptoStream(fout, _
           rijn.CreateEncryptor(rijnKey, rijnIV), CryptoStreamMode.Write)

        Console.WriteLine("Encrypting...")

        'Read from the input file, then encrypt and write to the output file.
        While rdlen < totlen
            len = fin.Read(bin, 0, 100)
            encStream.Write(bin, 0, len)
            rdlen = Convert.ToInt32(rdlen + len)
            Console.WriteLine("{0} bytes processed", rdlen)
        End While

        encStream.Close()
	fout.Close()
	fin.Close()
    End Sub


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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