Re: Encrypt code

From: Harry Simpson (hssimpson@nospamphgt.net)
Date: 08/06/02 

From: "Harry Simpson" <hssimpson@nospamphgt.net>
Date: Tue, 6 Aug 2002 15:33:57 -0500

Dan,

Already found it and converted it to VB.NET. But getting errors on the
decrypt side:
"FlushFinalBlock() method was called twice on a CryptoStream. This method
can only be called once"
Even tried to rename object in Decrypt.
Here's my(your) converted code:

Public Shared Function EncryptString(ByVal src As String) As String
        Dim p As Byte() = Encoding.ASCII.GetBytes(src.ToCharArray())
        Dim encodedBytes() As Byte

        Dim ms As New MemoryStream()
        Dim rv As New RijndaelManaged()
        Dim cs As New CryptoStream(ms, rv.CreateEncryptor(keyb, ivb),
CryptoStreamMode.Write)

        Try
            cs.Write(p, 0, p.Length)
            cs.FlushFinalBlock()
            encodedBytes = ms.ToArray()
        Finally
            ms.Close()
            cs.Close()
        End Try

        Return Convert.ToBase64String(encodedBytes)
End Function 'EncryptString

Public Shared Function DecryptString(ByVal src As String) As String
        Dim p As Byte() = Convert.FromBase64String(src)
        Dim initialText() As Byte = New [Byte](p.Length) {}

        Dim rv As New RijndaelManaged()
        Dim ms2 As New MemoryStream(p)
        Dim cs2 As New CryptoStream(ms2, rv.CreateDecryptor(keyb, ivb),
CryptoStreamMode.Read)

        Try
            cs2.Read(initialText, 0, initialText.Length)
            cs2.FlushFinalBlock()
        Finally
            ms2.Close()
            cs2.Close()
        End Try

        Dim sb As New StringBuilder()

        Dim i As Integer

        While i < initialText.Length
            sb.Append(CChar(initialText(i).ToString))
        End While
        Return sb.ToString()
End Function 'DecryptString

Thanks
Harry

"Dan Fergus" <dan@vbforest.com> wrote in message
news:eoQTozXPCHA.2688@tkmsftngp11...
> HArry,
>
> This is in C# but should be easy to convert to VB.NET
>
> http://www.fawcette.com/vsm/2002_08/online/hottips/fergus/
>
> Dan Fergus
> www.forestsoftwaregroup.com
>
> "Harry Simpson" <hssimpson@nospamphgt.net> wrote in message
> news:#2VTSyLPCHA.1756@tkmsftngp08...
> > Is there any VB.NET code demonstrating a very easy to implement
> > encrypt/decrypt class.
> >
> > Such that i can basically pass in the string and the function spits out
> the
> > encrypted string and vice versa. I've searched the sites and found a
web
> > service and a few C# samples writing to file and decrypting..
> >
> > I just wanna translate in code behind or functions.
> >
> > TIA
> > Harry
> >
> >
> >
>
>

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