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SymmetricAlgorithm.Create Method

Creates a default cryptographic object used to perform the symmetric algorithm.

Namespace:  System.Security.Cryptography
Assembly:  mscorlib (in mscorlib.dll)
'Declaration
Public Shared Function Create As SymmetricAlgorithm
'Usage
Dim returnValue As SymmetricAlgorithm 

returnValue = SymmetricAlgorithm.Create()

Return Value

Type: System.Security.Cryptography.SymmetricAlgorithm
A default cryptographic object used to perform the symmetric algorithm.

The following code 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

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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