Python 2/3真是令人沮丧...考虑下面这个例子:test.py
:
#!/usr/bin/env python
# -*- coding: utf-8 -*-
import sys
if sys.version_info[0] < 3:
text_type = unicode
binary_type = str
def b(x):
return x
def u(x):
return unicode(x, "utf-8")
else:
text_type = str
binary_type = bytes
import codecs
def b(x):
return codecs.latin_1_encode(x)[0]
def u(x):
return x
tstr = " ▲ "
sys.stderr.write(tstr)
sys.stderr.write("\n")
sys.stderr.write(str(len(tstr)))
sys.stderr.write("\n")
运行它:
$ python2.7 test.py
▲
5
$ python3.2 test.py
▲
3
太好了,我得到了两种不同的字符串大小。希望使用我在网络上找到的其中一种包装器能够有所帮助?
对于tstr = text_type(" ▲ ")
:
$ python2.7 test.py
Traceback (most recent call last):
File "test.py", line 21, in <module>
tstr = text_type(" ▲ ")
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 1: ordinal not in range(128)
$ python3.2 test.py
▲
3
For tstr = u(" ▲ ")
:
$ python2.7 test.py
Traceback (most recent call last):
File "test.py", line 21, in <module>
tstr = u(" ▲ ")
File "test.py", line 11, in u
return unicode(x)
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 1: ordinal not in range(128)
$ python3.2 test.py
▲
3
对于tstr = b(" ▲ ")
:
$ python2.7 test.py
▲
5
$ python3.2 test.py
Traceback (most recent call last):
File "test.py", line 21, in <module>
tstr = b(" ▲ ")
File "test.py", line 17, in b
return codecs.latin_1_encode(x)[0]
UnicodeEncodeError: 'latin-1' codec can't encode character '\u25b2' in position 1: ordinal not in range(256)
对于tstr = binary_type(" ▲ ")
:
$ python2.7 test.py
▲
5
$ python3.2 test.py
Traceback (most recent call last):
File "test.py", line 21, in <module>
tstr = binary_type(" ▲ ")
TypeError: string argument without an encoding
那么,这确实让事情变得简单。
那么,在Python 2.7和3.2中如何获得相同的字符串长度(在此示例中为3)?