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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
public static SymmetricAlgorithm Create ()
public static function Create () : SymmetricAlgorithm

Return Value

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

private static void EncryptData(String inName, String outName,
    ubyte rijnKey[], ubyte rijnIV[])
{
    //Create the file streams to handle the input and output files.
    FileStream fin = new FileStream(inName, FileMode.Open,
        FileAccess.Read);
    FileStream fout = new FileStream(outName, FileMode.OpenOrCreate,
        FileAccess.Write);
    fout.SetLength(0);

    //Create variables to help with read and write.
    //Following is intermediate storage for the encryption.
    ubyte bin[] = new ubyte[100]; 
    //Following is the total number of bytes written.
    long rdlen = 0;
    //Following is the total length of the input file.
    long totlen = fin.get_Length(); 
    //Following is the number of bytes to be written at a time.
    int len; 

    //Create the default implementation, which is RijndaelManaged.         
    SymmetricAlgorithm rijn = SymmetricAlgorithm.Create(); 
    CryptoStream encStream = 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 = rdlen + len;
        Console.WriteLine("{0} bytes processed", (System.Int64)rdlen);
    }
    encStream.Close();
    fout.Close();
    fin.Close();
} //EncryptData

Windows 98, Windows 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 .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0

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