从字节读取位 [英] Reading bits from bytes

问题描述

大家好.

我有点麻烦.我需要从一个字节读取位，其想法是我从流中读取一个字节，而我必须从该字节中读取位.
一个简单的示例是我读取了一个字节"A"，该字节将是字节"065".现在，我需要将其读取为"01000001"，实际上我需要将其读取为"0"，"1"，"0"，"0"，"0"，"0"，"0"，"1"或其他任何与True或False无关的解释.

假设地，该代码将计算一个文件中有多少"1"(真).

只要可以读取数据中的任何字节，我就可以使用任何编码，因为我需要读取的数据是上帝只知道什么.

我已经尝试了几件事，但是没有一件事情能正常工作.
我只是无法深入了解它.我读字节没问题，但似乎无法完成位部分.

我将不胜感激任何代码示例.

Hi all.

I''m having a little trouble. I need to read bits from a byte, the idea is that I read a byte from a stream and the I have to read bits from that byte.
A simple example would be I read a byte "A" which would be byte "065". Now I need to read that as "01000001", well actually I need to read it as "0","1","0","0","0","0","0","1" or any other interpretation like True or False it''s irrelevant.

Hypothetically, the code would count how many "1"(Trues) are there in a file.

I can live with any encoding as long as I can read any byte in the data as the data I need to read is God only knows what.

I''ve tried a couple of things but none of them worked as it should.
I just can''t get to the bottom of it. I read bytes no problem but just can''t seem to get the bits part done.

I''d appreciate any code sample. Thanks.

推荐答案

已阅读有关BitWise操作的文章，以确定各个位的状态.那是做事的原始方式.
http://visualbasic.about.com/od/usingvbnet/a/bitops01.htm [ ^ ]

现在我们还提供了BitArray，例如；

Have a read of this article on BitWise operations to determine the state of individual bits. That was the original way of doing things.
http://visualbasic.about.com/od/usingvbnet/a/bitops01.htm[^]

We now also have BitArray available e.g.;

Dim x As Byte
x = &H65
Dim ba As New BitArray({x})
MsgBox("Bit Status; " + ba.Get(7).ToString + _
                    " " + ba.Get(6).ToString + _
                    " " + ba.Get(5).ToString + _
                    " " + ba.Get(4).ToString + _
                    " " + ba.Get(3).ToString + _
                    " " + ba.Get(2).ToString + _
                    " " + ba.Get(1).ToString + _
                    " " + ba.Get(0).ToString)

这篇关于从字节读取位的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！