我如何在Python中指明字符串中的换行符,以便我可以将多行写入文本文件?
当前回答
在Python中,你可以只使用换行符,即\n
其他回答
Use:
"{}\n{}\n{}".format(
"line1",
"line2",
"line3"
)
我个人更喜欢这种形式。
您可以单独写入新行,也可以在单个字符串中写入,这样更容易。
示例1
输入
line1 = "hello how are you"
line2 = "I am testing the new line escape sequence"
line3 = "this seems to work"
你可以把“\n”分开写:
file.write(line1)
file.write("\n")
file.write(line2)
file.write("\n")
file.write(line3)
file.write("\n")
输出
hello how are you
I am testing the new line escape sequence
this seems to work
示例2
输入
正如其他人在之前的回答中指出的那样,将\n放在字符串中的相关点:
line = "hello how are you\nI am testing the new line escape sequence\nthis seems to work"
file.write(line)
输出
hello how are you
I am testing the new line escape sequence
this seems to work
在Python 3中,该语言会在平台的原生表示中为你编码换行符。这意味着在Windows上是\r\n,而在成熟的系统上只是\n。
即使在U*x系统上,以文本模式读取Windows行结束符的文件也会返回正确的文本结果,即在\n字符之前的任何\r字符都会被无声地删除。
如果需要完全控制文件中的字节,则可以使用二进制模式。然后,每个字节恰好对应一个字节,Python不执行任何转换。
>>> # Write a file with different line endings, using binary mode for full control
>>> with open('/tmp/demo.txt', 'wb') as wf:
... wf.write(b'DOS line\r\n')
... wf.write(b'U*x line\n')
... wf.write(b'no line')
10
9
7
>>> # Read the file as text
>>> with open('/tmp/demo.txt', 'r') as text:
... for line in text:
... print(line, end='')
DOS line
U*x line
no line
>>> # Or more demonstrably
>>> with open('/tmp/demo.txt', 'r') as text:
... for line in text:
... print(repr(line))
'DOS line\n'
'U*x line\n'
'no line'
>>> # Back to bytes!
>>> with open('/tmp/demo.txt', 'rb') as binary:
... for line in binary:
... print(line)
b'DOS line\r\n'
b'U*x line\n'
b'no line'
>>> # Open in binary, but convert back to text
>>> with open('/tmp/demo.txt', 'rb') as binary:
... for line in binary:
... print(line.decode('utf-8'), end='')
DOS line
U*x line
no line
>>> # Or again in more detail, with repr()
>>> with open('/tmp/demo.txt', 'rb') as binary:
... for line in binary:
... print(repr(line.decode('utf-8')))
'DOS line\r\n'
'U*x line\n'
'no line'
在Python中,你可以只使用换行符,即\n
Java字符串文字中的大多数转义字符在Python中也有效,例如“\r”和“\n”。