excel vba bit string to byte code example

Example 1: vba string to bits

'VBA function to convert text to a binary string representation:

Public Function TextToBinaryString$(s$)
    Dim c&, i&, lo&, bin$(0 To 255), d() As Byte
    Const ZEROS$ = "00000000"
    For c = 0 To 255
        bin(c) = ZEROS
        If c And 1& Then MidB$(bin(c), 15) = "1"
        If c And 2& Then MidB$(bin(c), 13) = "1"
        If c And 4& Then MidB$(bin(c), 11) = "1"
        If c And 8& Then MidB$(bin(c), 9) = "1"
        If c And 16& Then MidB$(bin(c), 7) = "1"
        If c And 32& Then MidB$(bin(c), 5) = "1"
        If c And 64& Then MidB$(bin(c), 3) = "1"
        If c And 128& Then MidB$(bin(c), 1) = "1"
    Next
    d = s
    lo = 1
    TextToBinaryString = Space$(LenB(s) * 8)
    For i = 0 To LenB(s) - 1 Step 2
        Mid$(TextToBinaryString, lo) = bin(d(i + 1))
        Mid$(TextToBinaryString, lo + 8) = bin(d(i))
        lo = lo + 16
    Next
End Function
            
'------------------------------------------------------------------------------
            
MsgBox TextToBinaryString("Hi")  '<--displays: 00000000010010000000000001101001

Example 2: vba bits to byte

'Extremely fast VBA function to convert a binary string to a Byte:

Function BitsToByte(bits$) As Byte
    Dim i&
    Static b() As Byte
    If LenB(bits) > 16 Then Exit Function
    If LenB(bits) = 16 Then
        b = bits
    Else
        b = String$(8 - Len(bits), "0") & bits
    End If
    For i = 0 To 14 Step 2
        BitsToByte = 2 * BitsToByte Or (b(i) Xor 48)
    Next
End Function


'Example:

MsgBox BitsToByte("00001100")		'<--displays: 12
MsgBox BitsToByte("10000001")		'<--displays: 129
'
'
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