vba check if specific bits are set in long integer code example

Example 1: excel vba are bits set in long

'Fast VBA function to test if specific bits are set 
'within a 32-bit Long integer. If ALL specified bits are set then 
'this function returns True. If ANY of the specified bits are
'not set then this function returns False.

'Bits are numbered from 0 to 31, so the first (least significant) bit
'is bit 0.

'Note: bits can be specified in any order.
'Note: any number of bits can be specified in one call.


Function LongBitsAreSet(theLong&, ParamArray bits()) As Boolean
    Static i&, b&()
    If UBound(bits) = -1 Then Exit Function
    If (Not Not b) = 0 Then
        ReDim b(0 To 30)
        For i = 0 To 30
            b(i) = 2 ^ i
        Next
    End If
    For i = 0 To UBound(bits)
        If bits(i) < 0 Then Exit Function
        If bits(i) > 30 Then Exit Function
        If (theLong And b(Int(bits(i)))) = 0 Then Exit Function
    Next
    LongBitsAreSet = True
End Function


'---------------------------------------------------------------------------------------------------------------------
MsgBox LongBitsAreSet(255, 7)                    '<--displays: True          255 = 00000000 00000000 00000000 11111111
MsgBox LongBitsAreSet(230, 0)                    '<--displays: False         230 = 00000000 00000000 00000000 11100110
MsgBox LongBitsAreSet(85, 0, 2, 6, 4)            '<--displays: True           85 = 00000000 00000000 00000000 01010101
MsgBox LongBitsAreSet(85, 0, 2, 5, 4)            '<--displays: False          85 = 00000000 00000000 00000000 01010101
MsgBox LongBitsAreSet(485, 2, 7, 5)              '<--displays: True          485 = 00000000 00000000 00000001 11100101
MsgBox LongBitsAreSet(24585, 14, 13, 3)          '<--displays: True        24585 = 00000000 00000000 01100000 00001001
MsgBox LongBitsAreSet(&H7D12EACB, 24, 26, 30, 7) '<--displays: True   2098391755 = 01111101 00010010 11101010 11001011 
'
'
'

Example 2: excel vba are bits set in integer

'Fast VBA function to test if specific bits are set 
'within a 16-bit Integer. If ALL specified bits are set then 
'this function returns True. If ANY of the specified bits are
'not set then this function returns False.

'Bits are numbered from 0 to 15, so the first (least significant) bit
'is bit 0.

'Note: bits can be specified in any order.
'Note: any number of bits can be specified in one call.


Function IntegerBitsAreSet(theInteger%, ParamArray bits()) As Boolean
    Static i&, b%()
    If UBound(bits) = -1 Then Exit Function
    If (Not Not b) = 0 Then
        ReDim b(0 To 14)
        For i = 0 To 14
            b(i) = 2 ^ i
        Next
    End If
    For i = 0 To UBound(bits)
        If bits(i) < 0 Then Exit Function
        If bits(i) > 14 Then Exit Function
        If (theInteger And b(Int(bits(i)))) = 0 Then Exit Function
    Next
    IntegerBitsAreSet = True
End Function


'----------------------------------------------------------------------------------------
MsgBox IntegerBitsAreSet(255, 7)           '<--displays: True     255 = 00000000 11111111
MsgBox IntegerBitsAreSet(230, 0)           '<--displays: False    230 = 00000000 11100110
MsgBox IntegerBitsAreSet(85, 0, 2, 6, 4)   '<--displays: True      85 = 00000000 01010101
MsgBox IntegerBitsAreSet(85, 0, 2, 5, 4)   '<--displays: False     85 = 00000000 01010101
MsgBox IntegerBitsAreSet(485, 2, 7, 5)     '<--displays: True     485 = 00000001 11100101
MsgBox IntegerBitsAreSet(24585, 14, 13, 3) '<--displays: True   24585 = 01100000 00001001        
'
'
'

Example 3: excel vba is bit set long

'Extremely fast VBA function to test if a specified bit is set 
'within a 32-bit Long integer.

'Bits are numbered from 0 to 31, so the first (least significant) bit
'is bit 0.

'Note: we do not inspect bit 31, the sign bit.
'Note: any number of bits can be specified in one call.


Function LongBitIsSet(theLong&, bit As Byte) As Boolean
    Static i&, b&()
    If (Not Not b) = 0 Then
        ReDim b(0 To 30)
        For i = 0 To 30
            b(i) = 2 ^ i
        Next
    End If
    If bit < 31 Then LongBitIsSet = theLong And b(bit)
End Function


'------------------------------------------------------------------
MsgBox LongBitIsSet(255, 7)             '<--displays: True
MsgBox LongBitIsSet(230, 0)             '<--displays: False
MsgBox LongBitIsSet(16384, 14)          '<--displays: True
MsgBox LongBitIsSet(-16383, 0)          '<--displays: True
MsgBox LongBitIsSet(&H7FFFFFFF, 0)      '<--displays: True

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