Function RSAVerschlüsseln(ByVal text As String)
        Dim xmlKeys As String 
        Dim xmlPublicKey As String
 
'The plaintext message in a byte array
        Dim PlainTextBArray As Byte()
'The cyphertext message in a byte array
        Dim CypherTextBArray As Byte()
 
        Dim rsa As New RSACryptoServiceProvider
 
         xmlKeys = rsa.ToXmlString(True)
 
        'Hold the public key to be used in the encryption procedure
        xmlPublicKey = rsa.ToXmlString(False)
 
        'get the public key so you can encrypt the message:
        rsa.FromXmlString(xmlPublicKey)
 
        'get the message
        Dim message As String = text
 
        If message.Length > 58 Then MsgBox("You must use fewer than 59" & _
          "characters") : Exit Function
 
        'transform message string into a byte array:
        PlainTextBArray = (New UnicodeEncoding).GetBytes(message)
 
        ' Encrypt 
        CypherTextBArray = rsa.Encrypt(PlainTextBArray, False)
 
        Dim test As String
 
 
        For i As Integer = 0 To CypherTextBArray.Length - 1
            test &= Chr(CypherTextBArray(i))
        Next i
 
        MsgBox(test)
 
        SetKey("Benutzername", test)
    End Function
 
 
 
    Function RSAEntschlüsseln(ByVal text As String)
        Dim xmlKeys As String 'A combination of both the public and     
        ' 'private keys  
        Dim rsa As New RSACryptoServiceProvider
 
        xmlKeys = rsa.ToXmlString(True)
 
        'get the keys, thereby creating an RSA object that's identical
        ' to the one used in the Form_Load event when the keys were first built
 
        RSA.FromXmlString(xmlKeys)
        Dim RestoredPlainText As Byte()
        Dim CypherTextBArray As Byte() = (New UnicodeEncoding).GetBytes(text)
        'create a byte array and then put the decrypted plaintext into it
        Try
            RestoredPlainText = rsa.Decrypt(CypherTextBArray, False)
        Catch ex As Security.SecurityException
            MsgBox(ex.ToString())
        End Try
 
        Dim test As String
 
        For i As Integer = 0 To (RestoredPlainText.Length - 1) Step 2
            test &= Chr(RestoredPlainText(i))
        Next i
 
    End Function