我如何修剪空白？

Question

是否有一个Python函数可以从字符串中修剪空格(空格和制表符)？

示例:\t example string\t→example string

Answer 1

双方空白:

s = "  \t a string example\t  "
s = s.strip()

右侧的空白:

s = s.rstrip()

左侧的空白:

s = s.lstrip()

正如thedz指出的那样,你可以提供一个参数来将任意字符剥离到这些函数中,如下所示:

s = s.strip(' \t\n\r')

这将去除任何空间,\t,\n,或\r从左侧字符,右手侧,或该字符串的两侧.

上面的示例仅从字符串的左侧和右侧删除字符串.如果您还要从字符串中间删除字符,请尝试re.sub:

import re
print re.sub('[\s+]', '', s)

那应该打印出来:

astringexample

Answer 2

trim调用Python 方法strip:

str.strip() #trim
str.lstrip() #ltrim
str.rstrip() #rtrim

Answer 3

对于前导和尾随空格:

s = '   foo    \t   '
print s.strip() # prints "foo"

否则,正则表达式起作用:

import re
pat = re.compile(r'\s+')
s = '  \t  foo   \t   bar \t  '
print pat.sub('', s) # prints "foobar"

Answer 4

您还可以使用非常简单的基本函数:str.replace(),使用空格和制表符:

>>> whitespaces = "   abcd ef gh ijkl       "
>>> tabs = "        abcde       fgh        ijkl"

>>> print whitespaces.replace(" ", "")
abcdefghijkl
>>> print tabs.replace(" ", "")
abcdefghijkl

简单易行.

Answer 5

#how to trim a multi line string or a file

s=""" line one
\tline two\t
line three """

#line1 starts with a space, #2 starts and ends with a tab, #3 ends with a space.

s1=s.splitlines()
print s1
[' line one', '\tline two\t', 'line three ']

print [i.strip() for i in s1]
['line one', 'line two', 'line three']




#more details:

#we could also have used a forloop from the begining:
for line in s.splitlines():
    line=line.strip()
    process(line)

#we could also be reading a file line by line.. e.g. my_file=open(filename), or with open(filename) as myfile:
for line in my_file:
    line=line.strip()
    process(line)

#moot point: note splitlines() removed the newline characters, we can keep them by passing True:
#although split() will then remove them anyway..
s2=s.splitlines(True)
print s2
[' line one\n', '\tline two\t\n', 'line three ']