不错的主要用于加密的vbs(asp)位移运算类


            <script language="vbscript"> ' Aother: 奔腾的心 '     QQ: 7180001 '   Date: 2008-01-17 Class mShift     Private m_lPower2(31)     Public Function RShift(ByVal lThis, ByVal lBits)         On Error Resume Next         Init         If (lBits <= 0) Then            RShift = lThis         ElseIf (lBits > 63) Then            ' .. error ...         ElseIf (lBits > 31) Then            RShift = 0         Else            If (lThis And m_lPower2(31 - lBits)) = m_lPower2(31 - lBits) Then               RShift = (lThis And (m_lPower2(31 - lBits) - 1)) * m_lPower2(lBits) Or  m_lPower2(31)            Else               RShift = (lThis And (m_lPower2(31 - lBits) - 1)) * m_lPower2(lBits)            End If         End If     End Function     Public Function LShift(ByVal lThis, ByVal lBits)         On Error Resume Next         Init         If (lBits <= 0) Then            LShift = lThis         ElseIf (lBits > 63) Then            ' ... error ...         ElseIf (lBits > 31) Then            LShift = 0         Else            If (lThis And m_lPower2(31)) = m_lPower2(31) Then               LShift = (lThis And &H7FFFFFFF) \ m_lPower2(lBits) Or m_lPower2(31 - lBits)            Else               LShift = lThis \ m_lPower2(lBits)            End If         End If     End Function     Private Sub Init()         On Error Resume Next         m_lPower2(0) = &H1&         m_lPower2(1) = &H2&         m_lPower2(2) = &H4&         m_lPower2(3) = &H8&         m_lPower2(4) = &H10&         m_lPower2(5) = &H20&         m_lPower2(6) = &H40&         m_lPower2(7) = &H80&         m_lPower2(8) = &H100&         m_lPower2(9) = &H200&         m_lPower2(10) = &H400&         m_lPower2(11) = &H800&         m_lPower2(12) = &H1000&         m_lPower2(13) = &H2000&         m_lPower2(14) = &H4000&         m_lPower2(15) = &H8000&         m_lPower2(16) = &H10000         m_lPower2(17) = &H20000         m_lPower2(18) = &H40000         m_lPower2(19) = &H80000         m_lPower2(20) = &H100000         m_lPower2(21) = &H200000         m_lPower2(22) = &H400000         m_lPower2(23) = &H800000         m_lPower2(24) = &H1000000         m_lPower2(25) = &H2000000         m_lPower2(26) = &H4000000         m_lPower2(27) = &H8000000         m_lPower2(28) = &H10000000         m_lPower2(29) = &H20000000         m_lPower2(30) = &H40000000         m_lPower2(31) = &H80000000     End Sub End Class Dim sft Set sft = New mShift MsgBox sft.RShift(200, 4) MsgBox sft.LShift(200, 4) Set sft = Nothing </script> <script language="javascript"> alert(200<<4); alert(200>>4); </script>