vb 位操作

[vb]代码库

'功能：    将字节变量循环左移n位
'入口参数：MoveByte 需要移位的字节变量
'          n 移动的位数
'返回值：  移位后的字节变量
Public Function ByteLeftMove(MoveByte As Byte, N As Integer) As Byte
Dim Intem As Byte '临时变量
Dim Intem1 As Byte '临时变量
Dim x As Integer, y As Integer
  Intem1 = MoveByte
  For x = 1 To N '移多少位就循环多少次
    For y = 8 To 1 Step -1 '从第八位(左边第一位)开始循环左移
      Select Case y
        Case 8
          '如果临时变量intem1的第八位是1,
          If (Intem1 And &H80) = &H80 Then
            '则将临时变量intem置1,
            Intem = &H1
          Else
            Intem = &H0 '反之置0
          End If
        Case 7
          '如果临时变量intem1的第七位是1,
          If (Intem1 And &H40) = &H40 Then
            '则将其第八位置1(其它位不变),
            Intem1 = Intem1 Or &H80
          Else
            '反之将第八位置0(其它位不变)
            Intem1 = Intem1 And &H7F
          End If
        Case 6
          '操作与上面相同
          If (Intem1 And &H20) = &H20 Then
            Intem1 = Intem1 Or &H40
          Else
            Intem1 = Intem1 And &HBF
          End If
        Case 5
          If (Intem1 And &H10) = &H10 Then
            Intem1 = Intem1 Or &H20
          Else
            Intem1 = Intem1 And &HDF
          End If
        Case 4
          If (Intem1 And &H8) = &H8 Then
            Intem1 = Intem1 Or &H10
          Else
            Intem1 = Intem1 And &HEF
          End If
        Case 3
          If (Intem1 And &H4) = &H4 Then
            Intem1 = Intem1 Or &H8
          Else
            Intem1 = Intem1 And &HF7
          End If
        Case 2
          If (Intem1 And &H2) = &H2 Then
            Intem1 = Intem1 Or &H4
          Else
            Intem1 = Intem1 And &HFB
          End If
        Case 1
          If (Intem1 And &H1) = &H1 Then
            Intem1 = Intem1 Or &H2
          Else
            Intem1 = Intem1 And &HFD
          End If
          If Intem = &H1 Then '移完第一位后,如果intem是1(即第八位是1)
            Intem1 = Intem1 Or &H1 '则将intem1的第一位置1
          Else
            Intem1 = Intem1 And &HFE '反之置0
          End If
      End Select
    Next y
  Next x
  ByteLeftMove = Intem1 '将intem1的值返回给函数名
End Function
 
 

'功能：    将字节变量循环右移n位
'入口参数：MoveByte 需要移位的字节变量
'          n 移动的位数
'返回值：  移位后的字节变量
Public Function ByteRightMOve(MoveByte As Byte, N As Integer) As Byte
Dim Intem As Byte '临时变量
Dim Intem1 As Byte '临时变量
Dim x As Integer, y As Integer
  Intem1 = MoveByte
  For x = 1 To N '移多少位就循环多少次
    For y = 1 To 8 Step 1 '从第一位(右边第一位)开始循环右移
      Select Case y
        Case 1
          '如果临时变量intem1的第一位是1,
          If (Intem1 And &H1) = &H1 Then
            '则将临时变量intem置1,
            Intem = &H1
          Else
            Intem = &H0 '反之置0
          End If
        Case 2
          '如果临时变量intem1的第二位是1,
          If (Intem1 And &H2) = &H2 Then
            '则将其第一位置1(其它位不变),
            Intem1 = Intem1 Or &H1
          Else
            '反之将第一位置0(其它位不变)
            Intem1 = Intem1 And &HFE
          End If
        Case 3
          '操作与上面相同
          If (Intem1 And &H4) = &H4 Then
            Intem1 = Intem1 Or &H2
          Else
            Intem1 = Intem1 And &HFD
          End If
        Case 4
          If (Intem1 And &H8) = &H8 Then
            Intem1 = Intem1 Or &H4
          Else
            Intem1 = Intem1 And &HFB
          End If
        Case 5
          If (Intem1 And &H10) = &H10 Then
            Intem1 = Intem1 Or &H8
          Else
            Intem1 = Intem1 And &HF7
          End If
        Case 6
          If (Intem1 And &H20) = &H20 Then
            Intem1 = Intem1 Or &H10
          Else
            Intem1 = Intem1 And &HEF
          End If
        Case 7
          If (Intem1 And &H40) = &H40 Then
            Intem1 = Intem1 Or &H20
          Else
            Intem1 = Intem1 And &HDF
          End If
        Case 8
          If (Intem1 And &H80) = &H80 Then
            Intem1 = Intem1 Or &H40
          Else
            Intem1 = Intem1 And &HBF
          End If
          If Intem = &H1 Then '移完第八位后,如果intem是1(即第一位是1)
            Intem1 = Intem1 Or &H80 '则将intem1的第八位置1
          Else
            Intem1 = Intem1 And &H7F '反之置0
          End If
      End Select
    Next y
  Next x
  ByteRightMOve = Intem1 '将intem1的值返回给函数名
End Function
 

'功能：     将字节数据的某一位置 1 或置 0
'入口参数： ByteData         数据  
'           BitNumber        位号
'           BitHandleType    位操作类型  0 置0 ， 1 置1
'返回值：   处理后的字节数据
Public Function BitHandle(ByVal BitHandleType As Long, ByVal ByteData As Byte, ByVal BitNumber As Long) As Byte
  Select Case BitHandleType
    '置0
    Case 0
      Select Case BitNumber
        '1位
        Case 1
          BitHandle = ByteData And &HFE
        '2位
        Case 2
          BitHandle = ByteData And &HFD
        '3位
        Case 3
          BitHandle = ByteData And &HFB
        '4位
        Case 4
          BitHandle = ByteData And &HF7
        '5位
        Case 5
          BitHandle = ByteData And &HEF
        '6位
        Case 6
          BitHandle = ByteData And &HDF
        '7位
        Case 7
          BitHandle = ByteData And &HBF
        '8位
        Case 8
          BitHandle = ByteData And &H7F
      End Select
    
    '置1
    Case 1
      Select Case BitNumber
        '1位
        Case 1
          BitHandle = ByteData Or &H1
        '2位
        Case 2
          BitHandle = ByteData Or &H2
        '3位
        Case 3
          BitHandle = ByteData Or &H4
        '4位
        Case 4
          BitHandle = ByteData Or &H8
        '5位
        Case 5
          BitHandle = ByteData Or &H10
        '6位
        Case 6
          BitHandle = ByteData Or &H20
        '7位
        Case 7
          BitHandle = ByteData Or &H40
        '8位
        Case 8
          BitHandle = ByteData Or &H80
      End Select
  End Select
End Function
 
'功能：     判断字节数据的某一位是 0 还是 1
'入口参数： ByteData 数据
'           BitNumber位号
'返回值：   检测位的数据
Public Function CheckBit(ByVal ByteData As Byte, BitNumber As Long) As Byte
  Select Case BitNumber
        '1位
        Case 1
          If (ByteData And &H1) = &H1 Then
            CheckBit = 1
          Else
            CheckBit = 0
          End If
        '2位
        Case 2
          If (ByteData And &H2) = &H2 Then
            CheckBit = 1
          Else
            CheckBit = 0
          End If
          
        '3位
        Case 3
          If (ByteData And &H4) = &H4 Then
            CheckBit = 1
          Else
            CheckBit = 0
          End If
          
        '4位
        Case 4
          If (ByteData And &H8) = &H8 Then
            CheckBit = 1
          Else
            CheckBit = 0
          End If
          
        '5位
        Case 5
          If (ByteData And &H10) = &H10 Then
            CheckBit = 1
          Else
            CheckBit = 0
          End If
          
        '6位
        Case 6
          If (ByteData And &H20) = &H20 Then
            CheckBit = 1
          Else
            CheckBit = 0
          End If
          
        '7位
        Case 7
          If (ByteData And &H40) = &H40 Then
            CheckBit = 1
          Else
            CheckBit = 0
          End If
          
        '8位
        Case 8
          If (ByteData And &H80) = &H80 Then
            CheckBit = 1
          Else
            CheckBit = 0
          End If
    
  End Select
End Function