python3中bytes与string的互相转换

首先来设置一个原始的字符串，

 Python 3.2.3 (default, Apr 11 2012, 07:15:24) [MSC v.1500 32 bit (Intel)] on win32

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 >>> website = 'http://www.cnblogs.com/txw1958/'

 >>> type(website)

 <class 'str'>

 >>> website

 'http://www.cnblogs.com/txw1958/'

 >>>

按utf-8的方式编码，转成bytes

 >>> website_bytes_utf8 = website.encode(encoding="utf-8")

 >>> type(website_bytes_utf8)

 <class 'bytes'>

 >>> website_bytes_utf8

 b'http://www.cnblogs.com/txw1958/'

 >>>

按gb2312的方式编码，转成bytes

 >>> website_bytes_gb2312 = website.encode(encoding="gb2312")

 >>> type(website_bytes_gb2312)

 <class 'bytes'>

 >>> website_bytes_gb2312

 b'http://www.cnblogs.com/txw1958/'

 >>>

解码成string，默认不填

 >>> website_string = website_bytes_utf8.decode()

 >>> type(website_string)

 <class 'str'>

 >>> website_string

 'http://www.cnblogs.com/txw1958/'

 >>>

 >>>

解码成string，使用gb2312的方式

 >>> website_string_gb2312 = website_bytes_gb2312.decode("gb2312")

 >>> type(website_string_gb2312)

 <class 'str'>

 >>> website_string_gb2312

 'http://www.cnblogs.com/txw1958/'

 >>>