vbspeed code example

Example: vba BitToLong

'Fast VBA function to converst binary string to a Long Integer:

Function BitsToLong&(bits$)
    Dim i&
    Static b() As Byte
    If LenB(bits) > 64 Then Exit Function
    If LenB(bits) = 64 Then
        b = bits
    Else
        b = String$(32 - Len(bits), "0") & bits
    End If
    For i = 2 To 62 Step 2
        BitsToLong = 2 * BitsToLong Or (b(i) Xor 48)
    Next
    If (b(0) Xor 48) Then BitsToLong = BitsToLong Or &H80000000
End Function

'-----------------------------------------------------------------------------

MsgBox BitsToLong("1")									'<--displays:  1    
MsgBox BitsToLong("10")									'<--displays:  2
MsgBox BitsToLong("0110")								'<--displays:  6
MsgBox BitsToLong("0100101")							'<--displays:  37
MsgBox BitsToLong("100000000000000000000")				'<--displays:  1048576
MsgBox BitsToLong("11111111111111111111111111111111")	'<--displays:  -1