GetBytes

Returns the pseudo-random key for this object.

 Public Function GetBytes(
	  ByVal cb As Long ) As Byte ( )

Parameters

cb

[ByVal] Long. The number of pseudo-random key bytes to generate.

Return Values

Remarks

The Rfc2898DeriveBytes class implements PBKDF2 functionality by using a pseudorandom number generator based on HMACSHA1. The Rfc2898DeriveBytes class takes a password, a salt, and an iteration count, and then generates keys through calls to the GetBytes method. Repeated calls to this method will not generate the same key; instead, appending two calls of the GetBytes method with a cb parameter value of 20 is the equivalent of calling the GetBytes method once with a cb parameter value of 40.

Exceptions

Exception	Condition
ArgumentOutOfRangeException	cb is out of range. This parameter requires a non-negative number.

Examples

The following example shows how to use the GetBytes method to get the key for an instance of Rfc2898DeriveBytes. This code example is part of a larger example provided for the Rfc2898DeriveBytes class.

    On Error GoTo Catch
    
    Dim K1 As Rfc2898DeriveBytes
    Dim K2 As Rfc2898DeriveBytes
    
    Set K1 = NewRfc2898DeriveBytes(Pwd1, Salt1, MyIterations)
    Set K2 = NewRfc2898DeriveBytes(Pwd1, Salt1)
    
    ' Encrypt the data.
    Dim EncAlg As TripleDES
    Dim EncryptionStream As New MemoryStream
    Dim Encrypt As CryptoStream
    Dim UtfD1() As Byte
    
    Set EncAlg = TripleDES.Create()
    EncAlg.Key = K1.GetBytes(16)
    Set Encrypt = NewCryptoStream(EncryptionStream, EncAlg.CreateEncryptor(), CryptoStreamMode.WriteMode)
    UtfD1 = NewUTF8Encoding(False).GetBytes(Data1)

See Also

Project CorLib Overview

Class Rfc2898DeriveBytes Overview