BitRotate

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BitRotate

执行旋转移位运算.

BitRotate ( value [, shift = 1 [, size = "W"]] )

参数

value	操作数的值.
shift	[可选] 左旋转位数 (负值右旋转). 如不指定, 默认为 1.
size	[可选] 决定旋转大小的字串, 默认为 (16 位). 见下文.

Size 参数 :

"B"	旋转位的低位字节(8 位).
"W"	旋转位的低位字(16 位).
"D"	旋转位的整个双字(32 位).

返回值

成功:	返回旋转所需要的位值.
失败:	设置 @error 为非 0 值, 表示"size"参数值无效.

备注

数字可以用十六进制表示法.

函数示例

#include <MsgBoxConstants.au3>
Example()
Func Example()
    ; Note: "b" is the symbol for byte.
    ; Assign a Local variable the bitwise left-rotate operation of 2.
    Local $iBitRotate1 = BitRotate(2, 1) ; 2 = 0010b left-rotated once -> 4 = 0100b
    ; Note: It is equivalent to do this: BitShift(2, -1)
    ; Display the result.
    MsgBox($MB_SYSTEMMODAL, "", $iBitRotate1)
    ; Assign a Local variable the bitwise right-rotate operation of 1.
    Local $iBitRotate2 = BitRotate(1, -1) ; 1 = 0001b right-rotated once -> 32768 (32 bits) = 1000 0000 0000 0000b
    ; Display the result.
    MsgBox($MB_SYSTEMMODAL, "", $iBitRotate2)
    ; Assign a Local variable the bitwise right-rotate operation of 14.
    Local $iBitRotate3 = BitRotate(14, -2) ; 14 = 1110b right-rotated twice -> 32771 (16 bits) = 1000 0000 0000 0011b
    ; Display the result.
    MsgBox($MB_SYSTEMMODAL, "", $iBitRotate3)
    ; Assign a Local variable the bitwise right-rotate operation of 14 on 32 bits.
    Local $iBitRotate4 = BitRotate(14, -2, "D")
    ; 14 = 1110b right-rotated twice -> -2147483645 (32 bits) = 1000 0000 0000 0000 0000 0000 0000 0011b (the first bit is signed)
    ; Display the result.
    MsgBox($MB_SYSTEMMODAL, "", $iBitRotate4)
EndFunc   ;==>Example