Need help to understand an algorithm

[ledaker]

Hi all, i have this algorithm for decrypt a message how i can translate the functions in red to c#

'CIPHER.CLS
Option Explicit

Private msKeyString As String
Private msText As String

'~~~.KeyString
'Une chaîne (clé) utilisée dans l'encryptage et le décryptage
Public Property Let KeyString(sKeyString As String)
    msKeyString = sKeyString
    Initialize
End Property

'~~~.Text
'Ecrit le texte Ã* encrypter ou décrypter
Public Property Let Text(sText As String)
    msText = sText
End Property

'Lit le texte qui a été encrypté ou décrypté
Public Property Get Text() As String
    Text = msText
End Property

'~~~.DoXor
'Méthode d'encryptage ou de décryptage par ou exclusif
Public Sub DoXor()
    Dim nC As Integer
    Dim nB As Integer
    Dim lI As Long
    lI = 1
    For lI = 1 To Len(msText)
        nC = Asc(Mid(msText, lI, 1))
        nB = Int(Rnd * 256)
        Mid(msText, lI, 1) = Chr(nC Xor nB)
    Next lI
    'MsgBox msText
End Sub

'~~~.Stretch (extension)
'Conversion de n'importe quelle chaîne en chaîne imprimable
'et visualisable
Public Sub Stretch()
    Dim nC As Integer
    Dim lI As Long
    Dim lJ As Long
    Dim nK As Integer
    Dim lA As Long
    Dim sB As String
    lA = Len(msText)
    sB = Space(lA + (lA + 2) \ 3)
    For lI = 1 To lA
        nC = Asc(Mid(msText, lI, 1))
        lJ = lJ + 1
        Mid(sB, lJ, 1) = Chr((nC And 63) + 59)
        Select Case lI Mod 3
        Case 1
            nK = nK Or ((nC \ 64) * 16)
        Case 2
            nK = nK Or ((nC \ 64) * 4)
        Case 0
            nK = nK Or (nC \ 64)
            lJ = lJ + 1
            Mid(sB, lJ, 1) = Chr(nK + 59)
            nK = 0
        End Select
    Next lI
    If lA Mod 3 Then
        lJ = lJ + 1
        Mid(sB, lJ, 1) = Chr(nK + 59)
    End If
    msText = sB
    'MsgBox msText
End Sub

'~~~.Shrink (Compression)
'Inverse de la méthode Décompactage (Stretch);
'le résultat peut contenir n'importe quelle valeur d'octet (0-255)
Public Sub Shrink()
    Dim nC As Integer
    Dim nD As Integer
    Dim nE As Integer
    Dim lA As Long
    Dim lB As Long
    Dim lI As Long
    Dim lJ As Long
    Dim lK As Long
    Dim sB As String
    
On Error GoTo Errora

    lA = Len(msText)
    lB = lA - 1 - (lA - 1) \ 4
    sB = Space(lB)
    For lI = 1 To lB
        lJ = lJ + 1
        nC = Asc(Mid(msText, lJ, 1)) - 59
        Select Case lI Mod 3
        Case 1
            lK = lK + 4
            If lK > lA Then lK = lA
            nE = Asc(Mid(msText, lK, 1)) - 59
            nD = ((nE \ 16) And 3) * 64
        Case 2
            nD = ((nE \ 4) And 3) * 64
        Case 0
            nD = (nE And 3) * 64
            lJ = lJ + 1
        End Select
        Mid(sB, lI, 1) = Chr(nC Or nD)
    Next lI
    msText = sB
    'MsgBox sB
    Exit Sub
Errora:
    'msText = ""
End Sub

'Initialise les nombres aléatoires en utilisant la chaîne clé
Private Sub Initialize()
    Dim nI As Double
    Randomize Rnd(-1)
    For nI = 1 To Len(msKeyString)
        Randomize Rnd(-Rnd * Asc(Mid(msKeyString, nI, 1)))
    Next nI
End Sub

[k_nemelka]

Je ne parle pas francais!

[cjard]

Tu peut parle un peut! Sufficient pour recommender essayer un VB.NET a C# traducteur?

Aussi, depuis quand il faut necessaire pour avoir les codes-sources plus facile (comme ici) en Anglais?!

'meilleur
public void DoXor(){
  int nC, nB;
  StringBuilder sb = new StringBuilder();

  foreach char c in msText
    sb.Append((char)(((int)c) ^ (Rnd * 256)) );

  msText = sb.ToString();
}

I think that's correct

[Marraco]

Tu peut parle un peut! Sufficient pour recommender essayer un VB.NET a C# traducteur?...

try:
http://www.developerfusion.com/tools.../csharp-to-vb/

[Marraco]

frenchs have good math, so probably also have good code.

try google translator

[ledaker]

Hi all, i am not french !! and thanks for all