測試過程比較啰嗦,可以直接看文章底部的結論
測試環境
python2.7.5
讀寫的文本
# -*- coding: utf-8 -*-
poetry = """
相思
唐代:王維
紅豆生南國,春來發幾枝。
願君多采撷,此物最相思。
"""
1、直接讀寫中文(正常)
# -*- coding: utf-8 -*-
# 寫入(正常)
f = open("相思.txt", "w")
f.write(poetry)
f.close()
# 讀取(正常)
f = open("相思.txt", "r")
print(f.read())
f.close()
2、引入
future
後讀寫中文(報錯)
# -*- coding: utf-8 -*-
from __future__ import unicode_literals, print_function
# 寫入(報錯)
f = open("相思.txt", "w")
f.write(poetry)
f.close()
"""
Traceback (most recent call last):
File "code_demo.py", line 18, in <module>
f.write(poetry)
UnicodeEncodeError: 'ascii' codec can't encode characters in position 1-2:
ordinal not in range(128)
"""
# 讀取(正常)
f = open("相思.txt", "r")
print(f.read())
f.close()
3、引入
future
後通過
io
讀寫中文(正常)
# -*- coding: utf-8 -*-
from __future__ import unicode_literals, print_function
import io
# 寫入(正常)
f = io.open("相思.txt", "w")
f.write(poetry)
f.close()
# 讀取(正常)
f = io.open("相思.txt", "r")
print(f.read())
f.close()
4、使用codecs直接讀寫中文(正常)
# -*- coding: utf-8 -*-
import codecs
# 寫入(正常)
f = codecs.open("相思.txt", "w")
f.write(poetry)
f.close()
# 讀取(正常)
f = codecs.open("相思.txt", "r")
print(f.read())
f.close()
5、引入
future
後使用codecs讀寫中文(報錯)
# -*- coding: utf-8 -*-
from __future__ import unicode_literals, print_function
import codecs
# 寫入(報錯)
f = codecs.open("相思.txt", "w")
f.write(poetry)
f.close()
"""
Traceback (most recent call last):
File "code_demo.py", line 19, in <module>
f.write(poetry)
UnicodeEncodeError: 'ascii' codec can't encode characters in position 1-2:
ordinal not in range(128)
"""
# 讀取(正常)
f = codecs.open("相思.txt", "r")
print(f.read())
f.close()
6、引入
future
後使用codecs指定編碼後讀寫中文(正常)
# -*- coding: utf-8 -*-
from __future__ import unicode_literals, print_function
import codecs
# 寫入(正常) 需要制定編碼 "utf-8"
f = codecs.open("相思.txt", "w", "utf-8")
f.write(poetry)
f.close()
# 讀取(正常)
f = codecs.open("相思.txt", "r")
print(f.read())
f.close()
總結
環境 | 編碼 | 讀寫方式 | 讀情況 | 寫情況 |
預設 | ASCII | open | - | |
引入future | unicode | 報錯 | ||
io.open | ||||
codecs.open | ||||
codecs.open指定編碼utf-8 |
是以,預設編碼是ASCII碼,正常情況下直接讀寫是沒有問題的,如果引入新特性future.unicode_literals之後,檔案的中文編碼變成了unicode,原來的不支援unicode讀寫的方式就會報錯
在Python2.7 中,内建的 open函數是沒有encoding參數的,不能指定編碼,隻能通過io.open 來讀寫unicode編碼的中文,或者通過codecs.open 指定編碼方式
在Python3之後,内建的 open函數添加了encoding參數,可以直接指定編碼,當然Python3的預設編碼已經改為了unicode,沒有那麼多問題