[已解决]Python中b'1'是什么意思？

Judie

为什么前面有个b啊？这个b是个什么玩意儿？求解，谢谢宁www！

最佳答案

月排行榜 / 总排行榜

阿奇_o

2021-5-7 09:37:36

第一印象：你们都学的什么奇怪的东西呀，dtype='S'

第二反应：从结果上看，应该是 字节存储 byte ，可为啥 dtype='S' ？ 后面还显示为 |S1 ?

于是去查了一下，
StackOverflow有人回答：

The |S1 and |S2 strings are data type descriptors; the first means the array holds strings of length 1, the second of length 2. 
The | pipe symbol is the byteorder flag; in this case there is no byte order flag needed, so it's set to |, meaning not applicable.

官方：不推荐！

'S', 'a' zero-terminated bytes (not recommended)

等等，这个 zero-terminated bytes 又是神马鬼？？
再查.....

 维基百科：
In computer programming, a null-terminated string is a character string stored as an array containing the characters and terminated with a null character (a character with a value of zero, called NUL in this article). 
Alternative names are C string, which refers to the C programming language and ASCIIZ (although C can use encodings other than ASCII).

其他参考：A null-terminated byte string (NTBS) is a sequence of nonzero bytes followed by a byte with value zero (the terminating null character).
Each byte in a byte string encodes one character of some character set.
For example, the character array {'\x63','\x61','\x74','\0'} is an NTBS holding the string "cat" in ASCII encoding.

总结：这种存储格式，原来是 一串非零字节序列数组，如上面例子的'\x63','\x61','\x74' 这些是ASCII码，
然后 附带跟着一个0值位（故叫 null-terminated 或 zero-terminated），即上面例子的 '\0' 。

ps: 我为啥要找这一圈。。官方都不推荐的数据类型。。

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wp231957

bytes型数据

阿奇_o

第一印象：你们都学的什么奇怪的东西呀，dtype='S'

第二反应：从结果上看，应该是 字节存储 byte ，可为啥 dtype='S' ？ 后面还显示为 |S1 ?

于是去查了一下，
StackOverflow有人回答：

The |S1 and |S2 strings are data type descriptors; the first means the array holds strings of length 1, the second of length 2. 
The | pipe symbol is the byteorder flag; in this case there is no byte order flag needed, so it's set to |, meaning not applicable.

官方：不推荐！

'S', 'a' zero-terminated bytes (not recommended)

等等，这个 zero-terminated bytes 又是神马鬼？？
再查.....

 维基百科：
In computer programming, a null-terminated string is a character string stored as an array containing the characters and terminated with a null character (a character with a value of zero, called NUL in this article). 
Alternative names are C string, which refers to the C programming language and ASCIIZ (although C can use encodings other than ASCII).

其他参考：A null-terminated byte string (NTBS) is a sequence of nonzero bytes followed by a byte with value zero (the terminating null character).
Each byte in a byte string encodes one character of some character set.
For example, the character array {'\x63','\x61','\x74','\0'} is an NTBS holding the string "cat" in ASCII encoding.

总结：这种存储格式，原来是 一串非零字节序列数组，如上面例子的'\x63','\x61','\x74' 这些是ASCII码，
然后 附带跟着一个0值位（故叫 null-terminated 或 zero-terminated），即上面例子的 '\0' 。

ps: 我为啥要找这一圈。。官方都不推荐的数据类型。。

Stubborn

阿奇_o 发表于 2021-5-7 09:37
第一印象：你们都学的什么奇怪的东西呀，dtype='S'

第二反应：从结果上看，应该是 字节存储 byte ，可为 ...

'\0' 是字符串的结束标志

Judie

阿奇_o 发表于 2021-5-6 20:37
第一印象：你们都学的什么奇怪的东西呀，dtype='S'

第二反应：从结果上看，应该是 字节存储 byte ，可为 ...

字节存储 byte 又是什么ww

Judie

wp231957 发表于 2021-5-6 17:39
bytes型数据

bytes型数据又是什么？为什么这里出来的会是byte型数据呢？