字符串常用操作
- 移除空白
- 分割
- 长度
- 索引
- 切片
class str(basestring):
"""
str(object='') -> string Return a nice string representation of the object.
If the argument is a string, the return value is the same object.
"""
def capitalize(self):
""" 首字母变大写 """
"""
S.capitalize() -> string Return a copy of the string S with only its first character
capitalized.
"""
return "" def center(self, width, fillchar=None):
""" 内容居中，width：总长度；fillchar：空白处填充内容，默认无 """
"""
S.center(width[, fillchar]) -> string Return S centered in a string of length width. Padding is
done using the specified fill character (default is a space)
"""
return "" def count(self, sub, start=None, end=None):
""" 子序列个数 """
"""
S.count(sub[, start[, end]]) -> int Return the number of non-overlapping occurrences of substring sub in
string S[start:end]. Optional arguments start and end are interpreted
as in slice notation.
"""
return 0 def decode(self, encoding=None, errors=None):
""" 解码 """
"""
S.decode([encoding[,errors]]) -> object Decodes S using the codec registered for encoding. encoding defaults
to the default encoding. errors may be given to set a different error
handling scheme. Default is 'strict' meaning that encoding errors raise
a UnicodeDecodeError. Other possible values are 'ignore' and 'replace'
as well as any other name registered with codecs.register_error that is
able to handle UnicodeDecodeErrors.
"""
return object() def encode(self, encoding=None, errors=None):
""" 编码，针对unicode """
"""
S.encode([encoding[,errors]]) -> object Encodes S using the codec registered for encoding. encoding defaults
to the default encoding. errors may be given to set a different error
handling scheme. Default is 'strict' meaning that encoding errors raise
a UnicodeEncodeError. Other possible values are 'ignore', 'replace' and
'xmlcharrefreplace' as well as any other name registered with
codecs.register_error that is able to handle UnicodeEncodeErrors.
"""
return object() def endswith(self, suffix, start=None, end=None):
""" 是否以 xxx 结束 """
"""
S.endswith(suffix[, start[, end]]) -> bool Return True if S ends with the specified suffix, False otherwise.
With optional start, test S beginning at that position.
With optional end, stop comparing S at that position.
suffix can also be a tuple of strings to try.
"""
return False def expandtabs(self, tabsize=None):
""" 将tab转换成空格，默认一个tab转换成8个空格 """
"""
S.expandtabs([tabsize]) -> string Return a copy of S where all tab characters are expanded using spaces.
If tabsize is not given, a tab size of 8 characters is assumed.
"""
return "" def find(self, sub, start=None, end=None):
""" 寻找子序列位置，如果没找到，返回 -1 """
"""
S.find(sub [,start [,end]]) -> int Return the lowest index in S where substring sub is found,
such that sub is contained within S[start:end]. Optional
arguments start and end are interpreted as in slice notation. Return -1 on failure.
"""
return 0 def format(*args, **kwargs): # known special case of str.format
""" 字符串格式化，动态参数，将函数式编程时细说 """
"""
S.format(*args, **kwargs) -> string Return a formatted version of S, using substitutions from args and kwargs.
The substitutions are identified by braces ('{' and '}').
"""
pass def index(self, sub, start=None, end=None):
""" 子序列位置，如果没找到，报错 """
S.index(sub [,start [,end]]) -> int Like S.find() but raise ValueError when the substring is not found.
"""
return 0 def isalnum(self):
""" 是否是字母和数字 """
"""
S.isalnum() -> bool Return True if all characters in S are alphanumeric
and there is at least one character in S, False otherwise.
"""
return False def isalpha(self):
""" 是否是字母 """
"""
S.isalpha() -> bool Return True if all characters in S are alphabetic
and there is at least one character in S, False otherwise.
"""
return False def isdigit(self):
""" 是否是数字 """
"""
S.isdigit() -> bool Return True if all characters in S are digits
and there is at least one character in S, False otherwise.
"""
return False def islower(self):
""" 是否小写 """
"""
S.islower() -> bool Return True if all cased characters in S are lowercase and there is
at least one cased character in S, False otherwise.
"""
return False def isspace(self):
"""
S.isspace() -> bool Return True if all characters in S are whitespace
and there is at least one character in S, False otherwise.
"""
return False def istitle(self):
"""
S.istitle() -> bool Return True if S is a titlecased string and there is at least one
character in S, i.e. uppercase characters may only follow uncased
characters and lowercase characters only cased ones. Return False
otherwise.
"""
return False def isupper(self):
"""
S.isupper() -> bool Return True if all cased characters in S are uppercase and there is
at least one cased character in S, False otherwise.
"""
return False def join(self, iterable):
""" 连接 """
"""
S.join(iterable) -> string Return a string which is the concatenation of the strings in the
iterable. The separator between elements is S.
"""
return "" def ljust(self, width, fillchar=None):
""" 内容左对齐，右侧填充 """
"""
S.ljust(width[, fillchar]) -> string Return S left-justified in a string of length width. Padding is
done using the specified fill character (default is a space).
"""
return "" def lower(self):
""" 变小写 """
"""
S.lower() -> string Return a copy of the string S converted to lowercase.
"""
return "" def lstrip(self, chars=None):
""" 移除左侧空白 """
"""
S.lstrip([chars]) -> string or unicode Return a copy of the string S with leading whitespace removed.
If chars is given and not None, remove characters in chars instead.
If chars is unicode, S will be converted to unicode before stripping
"""
return "" def partition(self, sep):
""" 分割，前，中，后三部分 """
"""
S.partition(sep) -> (head, sep, tail) Search for the separator sep in S, and return the part before it,
the separator itself, and the part after it. If the separator is not
found, return S and two empty strings.
"""
pass def replace(self, old, new, count=None):
""" 替换 """
"""
S.replace(old, new[, count]) -> string Return a copy of string S with all occurrences of substring
old replaced by new. If the optional argument count is
given, only the first count occurrences are replaced.
"""
return "" def rfind(self, sub, start=None, end=None):
"""
S.rfind(sub [,start [,end]]) -> int Return the highest index in S where substring sub is found,
such that sub is contained within S[start:end]. Optional
arguments start and end are interpreted as in slice notation. Return -1 on failure.
"""
return 0 def rindex(self, sub, start=None, end=None):
"""
S.rindex(sub [,start [,end]]) -> int Like S.rfind() but raise ValueError when the substring is not found.
"""
return 0 def rjust(self, width, fillchar=None):
"""
S.rjust(width[, fillchar]) -> string Return S right-justified in a string of length width. Padding is
done using the specified fill character (default is a space)
"""
return "" def rpartition(self, sep):
"""
S.rpartition(sep) -> (head, sep, tail) Search for the separator sep in S, starting at the end of S, and return
the part before it, the separator itself, and the part after it. If the
separator is not found, return two empty strings and S.
"""
pass def rsplit(self, sep=None, maxsplit=None):
"""
S.rsplit([sep [,maxsplit]]) -> list of strings Return a list of the words in the string S, using sep as the
delimiter string, starting at the end of the string and working
to the front. If maxsplit is given, at most maxsplit splits are
done. If sep is not specified or is None, any whitespace string
is a separator.
"""
return [] def rstrip(self, chars=None):
"""
S.rstrip([chars]) -> string or unicode Return a copy of the string S with trailing whitespace removed.
If chars is given and not None, remove characters in chars instead.
If chars is unicode, S will be converted to unicode before stripping
"""
return "" def split(self, sep=None, maxsplit=None):
""" 分割， maxsplit最多分割几次 """
"""
S.split([sep [,maxsplit]]) -> list of strings Return a list of the words in the string S, using sep as the
delimiter string. If maxsplit is given, at most maxsplit
splits are done. If sep is not specified or is None, any
whitespace string is a separator and empty strings are removed
from the result.
"""
return [] def splitlines(self, keepends=False):
""" 根据换行分割 """
"""
S.splitlines(keepends=False) -> list of strings Return a list of the lines in S, breaking at line boundaries.
Line breaks are not included in the resulting list unless keepends
is given and true.
"""
return [] def startswith(self, prefix, start=None, end=None):
""" 是否起始 """
"""
S.startswith(prefix[, start[, end]]) -> bool Return True if S starts with the specified prefix, False otherwise.
With optional start, test S beginning at that position.
With optional end, stop comparing S at that position.
prefix can also be a tuple of strings to try.
"""
return False def strip(self, chars=None):
""" 移除两段空白 """
"""
S.strip([chars]) -> string or unicode Return a copy of the string S with leading and trailing
whitespace removed.
If chars is given and not None, remove characters in chars instead.
If chars is unicode, S will be converted to unicode before stripping
"""
return "" def swapcase(self):
""" 大写变小写，小写变大写 """
"""
S.swapcase() -> string Return a copy of the string S with uppercase characters
converted to lowercase and vice versa.
"""
return "" def title(self):
"""
S.title() -> string Return a titlecased version of S, i.e. words start with uppercase
characters, all remaining cased characters have lowercase.
"""
return "" def translate(self, table, deletechars=None):
"""
转换，需要先做一个对应表，最后一个表示删除字符集合
intab = "aeiou"
outtab = ""
trantab = maketrans(intab, outtab)
str = "this is string example....wow!!!"
print str.translate(trantab, 'xm')
""" """
S.translate(table [,deletechars]) -> string Return a copy of the string S, where all characters occurring
in the optional argument deletechars are removed, and the
remaining characters have been mapped through the given
translation table, which must be a string of length 256 or None.
If the table argument is None, no translation is applied and
the operation simply removes the characters in deletechars.
"""
return "" def upper(self):
"""
S.upper() -> string Return a copy of the string S converted to uppercase.
"""
return "" def zfill(self, width):
"""方法返回指定长度的字符串，原字符串右对齐，前面填充0。"""
"""
S.zfill(width) -> string Pad a numeric string S with zeros on the left, to fill a field
of the specified width. The string S is never truncated.
"""
return "" def _formatter_field_name_split(self, *args, **kwargs): # real signature unknown
pass def _formatter_parser(self, *args, **kwargs): # real signature unknown
pass def __add__(self, y):
""" x.__add__(y) <==> x+y """
pass def __contains__(self, y):
""" x.__contains__(y) <==> y in x """
pass def __eq__(self, y):
""" x.__eq__(y) <==> x==y """
pass def __format__(self, format_spec):
"""
S.__format__(format_spec) -> string Return a formatted version of S as described by format_spec.
"""
return "" def __getattribute__(self, name):
""" x.__getattribute__('name') <==> x.name """
pass def __getitem__(self, y):
""" x.__getitem__(y) <==> x[y] """
pass def __getnewargs__(self, *args, **kwargs): # real signature unknown
pass def __getslice__(self, i, j):
"""
x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported.
"""
pass def __ge__(self, y):
""" x.__ge__(y) <==> x>=y """
pass def __gt__(self, y):
""" x.__gt__(y) <==> x>y """
pass def __hash__(self):
""" x.__hash__() <==> hash(x) """
pass def __init__(self, string=''): # known special case of str.__init__
"""
str(object='') -> string Return a nice string representation of the object.
If the argument is a string, the return value is the same object.
# (copied from class doc)
"""
pass def __len__(self):
""" x.__len__() <==> len(x) """
pass def __le__(self, y):
""" x.__le__(y) <==> x<=y """
pass def __lt__(self, y):
""" x.__lt__(y) <==> x<y """
pass def __mod__(self, y):
""" x.__mod__(y) <==> x%y """
pass def __mul__(self, n):
""" x.__mul__(n) <==> x*n """
pass @staticmethod # known case of __new__
def __new__(S, *more):
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass def __ne__(self, y):
""" x.__ne__(y) <==> x!=y """
pass def __repr__(self):
""" x.__repr__() <==> repr(x) """
pass def __rmod__(self, y):
""" x.__rmod__(y) <==> y%x """
pass def __rmul__(self, n):
""" x.__rmul__(n) <==> n*x """
pass def __sizeof__(self):
""" S.__sizeof__() -> size of S in memory, in bytes """
pass def __str__(self):
""" x.__str__() <==> str(x) """
pass strstr
EX:
移除空格——strip、rstrip、lstrip
#字符串去除空格 #去除左右空格
s1 = " hello，world! "
result = s1.strip()
print(result) #去除左空格
s1 = " hello，world! "
result = s1.lstrip()
print(result) #去除右空格
s1 = " hello, world! "
result = s1.rstrip()
print(result)
strip
分割&切割——partition、rpartition\split、rsplit、splitlines
#字符串操作——分割、切割 #分割（前中后3部分），返回结果类型为元组
s1 = " hello, world! "
#以‘l’分割字符
print(s1.partition('l'))
#rpartition分割（前中后3部分），返回结果类型为元组
s1 = " hello, world! "
#以‘l’分割字符
print(s1.rpartition('l')) ---------------------------------------------------- # split字符串的切割，return结果是列表
s1 = " hello, world! "
result = s1.split(sep='o',maxsplit=2)
print(result)
#[' hell', ', w', 'rld! '] # splitlines字符串以换行符切割，return结果是列表
s1 = " hello, \nworld! "
result = s1.splitlines(keepends=False)
print(result)
#[' hello, ', 'world! ']
split