CONVERSION DÉCIMALE/BINAIRE & BINAIRE/DÉCIMALE

' CONVERSION D'UNE CHAINE BINAIRE EN VALEUR DECIMALE
'
' Binary : du type "100111001" (longeur max 32 caracteres)
' NbBits : nombre de bits a considérer
' Signed : la chaine binaire désigne une valeur décimale signée ou non
Public Function BinaryToDecimal(Binary As String, NbBits As Byte, Signed As Boolean) As Long
    Dim i As Byte
    BinaryToDecimal = 0
    If NbBits <= 1 Or NbBits > 32 Then Exit Function
    If Len(Binary) > NbBits Or Len(Binary) > 32 Then Exit Function
    Binary = Right("00000000000000000000000000000000" & Binary, NbBits)
    If Signed = False Then
        For i = 0 To Len(Binary) - 1
            BinaryToDecimal = BinaryToDecimal + Val(Mid(Binary, Len(Binary) - i, 1)) * 2 ^ i
        Next i
    Else
        For i = 0 To Len(Binary) - 2
            BinaryToDecimal = BinaryToDecimal + Val(Mid(Binary, Len(Binary) - i, 1)) * 2 ^ i
        Next i
        If Left(Binary, 1) = "1" Then
            BinaryToDecimal = -((2 ^ (NbBits - 1)) - BinaryToDecimal)
        End If
    End If
End Function
 
' CONVERSION D'UNE VALEUR DECIMALE EN CHAINE BINAIRE
'
' Decimal : valeur décimale à convertir
' NbBits : nombre de bits a considérer
' Completed : la chaine binaire est complétée de 0 si necéssaire
Public Function DecimalToBinary(Decimale As Long, NbBits As Byte, Optional Completed As Boolean) As String
    Dim L, B As String
    DecimalToBinary = ""
    If Decimale > (2 ^ NbBits) - 1 Then Exit Function
    If Decimale < -(2 ^ (NbBits - 1)) - 1 Then Exit Function
    If NbBits > 32 Then Exit Function
        
    If Decimale < 0 Then
        Decimale = 2 ^ NbBits + Decimale
    End If
    
    If Decimale = 0 Or Decimale = 1 Then L = "" Else L = 1
    Do
        If Decimale Mod 2 = 0 Then B = "0" Else B = "1"
        DecimalToBinary = DecimalToBinary & B
        Decimale = Decimale \ 2
    Loop Until Decimale <= 1
    DecimalToBinary = StrReverse(DecimalToBinary & L)
    If Completed = True Then
        DecimalToBinary = Right("00000000000000000000000000000000" & DecimalToBinary, NbBits)
    End If
End Function