CSV:什么时候unicode不是unicode？

Question

为什么writerow()说我要通过str，当我经过unicode时

import io
import csv

with io.open('test.csv', 'w', encoding="utf-8") as f:
    writer = csv.writer(f)
    x = [unicode(v, 'utf8') for v in ['id:ID', 'pos:string', 'definition:string', ':LABEL']]
    print x
    print type(x[0])
    writer.writerow(x)

[u'id:ID', u'pos:string', u'definition:string', u':LABEL']
<type 'unicode'>
Traceback (most recent call last):
 File "testcsv.py", line 9, in <module>
     writer.writerow(x)
  TypeError: write() argument 1 must be unicode, not str

Answer 1

python 2中的csv模块不处理unicode。关于如何创建您自己的unicode处理程序的python2文档举一个例子。

一个更好的选择是安装backports.csv模块，它允许您的python2代码使用新的python3Unicode api，它处理backports.csv。

使用pip install backports.csv安装库后，此代码在python 2中工作：

>>> import io
>>> from backports import csv
>>> with io.open('test.csv', 'w', encoding="utf-8") as f:
>>>     writer = csv.writer(f)
>>>     x = [unicode(v, 'utf8') for v in ['id:ID', 'pos:string', 'definition:string', ':LABEL']]
>>>     print x
>>>     print type(x[0])
>>>     writer.writerow(x)
[u'id:ID', u'pos:string', u'definition:string', u':LABEL']
<type 'unicode'>

>>> with io.open('test.csv', encoding="utf-8") as f:
>>>     print f.read()
id:ID,pos:string,definition:string,:LABEL