一、字符串
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 = "12345"
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
str
str
str
1. capitalize 首字符大写
def capitalize(self)： a = ‘xinzi‘ print(a.capitalize()) Xinzi
2. casefold 字符小写
def casefold(self)： S.casefold() -> str a = ‘XinZi‘ print(a.casefold()) xinzi
3. center 居中填充字符
def center(self, width, fillchar=None): width:字符串的总宽度 fillchar：填充字符 a = ‘xinzi‘ print(a.center(20,‘*‘)) *******xinzi********
4. count 返回字符出现次数
str.count(sub, start= 0,end=len(string)) sub -- 搜索的子字符串 start -- 字符串开始搜索的位置。默认为第一个字符,第一个字符索引值为0。 end -- 字符串中结束搜索的位置。字符中第一个字符的索引为 0。默认为字符串的最后一个位置。 a = ‘this is string example....wow!!!‘ sub = ‘i‘ print(a.count(sub,4,40)) 2
5. encode 指定编码格式解码
str.decode(encoding=‘UTF-8‘,errors=‘strict‘) encoding -- 要使用的编码，如"UTF-8"。 errors -- 设置不同错误的处理方案。默认为 ‘strict‘,意为编码错误引起一个UnicodeError。 其他可能得值有 ‘ignore‘, ‘replace‘, ‘xmlcharrefreplace‘, ‘backslashreplace‘ 以及通过 codecs.register_error() 注册的任何值。 a = ‘信子‘ result = a.encode(‘gbk‘) print(result ) b‘\xd0\xc5\xd7\xd3‘
6. endswith 判断字符串是否以指定字符结尾 ，是为Ture，否则False
str.endswith(suffix[, start[, end]]) suffix -- 该参数可以是一个字符串或者是一个元素。 start -- 字符串中的开始位置。 end -- 字符中结束位置。 a = ‘this is string example....wow!!‘ suffix = ‘wow!!‘ print(a.endswith(suffix)) suf = ‘is‘ print(a.endswith(suf,2,4)) print(a.endswith(suf,2,6)) True True False
7. expandtabs 把字符中tab符号转换为空格,默认为8
str.expandtabs(tabsize=8) tabsize -- 指定转换字符串中的 tab 符号(‘\t‘)转为空格的字符数。 a = ‘this is \tstring example....wow!!‘ print(a) print(a.expandtabs()) print(a.expandtabs(20)) this is string example....wow!! this is string example....wow!! this is string example....wow!!
8. find 查找指定字符
str.find(str, beg=0, end=len(string)) str -- 指定检索的字符串 beg -- 开始索引，默认为0。 end -- 结束索引，默认为字符串的长度 a = ‘this is string example....wow!!‘ str1 = ‘exam‘ print(a.find(str1)) print(a.find(str1,10)) print(a.find(str1,40)) 15 15 -1 #找不到返回“ -1”值
9. format 字符串拼接，置换
def format(*args, **kwargs):
a = ‘this is string {0} ‘
result = a.format(‘wow!!‘)
print(result)
name = ‘this is string {name} {aa}‘
result2 = name.format(name=‘example‘,aa=‘wow!!‘)
print(result2)
this is string wow!!
this is string example wow!!
10. format_map
11. index 查找，没有则报错
str.index(str, beg=0, end=len(string)) str -- 指定检索的字符串 beg -- 开始索引，默认为0。 end -- 结束索引，默认为字符串的长度。 a = ‘this is string example....wow!!‘ b = ‘exam‘ print (a.index(b)) print (a.index(b,10)) print (a.index(b,40)) 15 15 ValueError: substring not found
12. rindex 类似index 从右边开始。
13. isalnum 判断字符串是否由字母和数字组成
str.isa1num() a = ‘this is string example....wow!!‘ b = ‘exam1239‘ print(a.isalnum()) print(b.isalnum()) False True
14. isalpha 判断是否由字母组成。
15. isdecimal 判断是否只包含十进制数字
str.isdecimal() 方法检查字符串是否只包含十进制字符。这种方法只存在于unicode对象 str =u‘this8890‘ #定义一个十进制字符串，只需要在字符串前添加 ‘u‘ 前缀即可 str2 =u‘83908400‘ print(str.isdecimal()) print(str2.isdecimal()) False True
16.isdigit 判断是否只有数字
17. isidentifier
18. islower 检测字符是否只由小写字母组成。
19. isnumeric 检测字符串是否只有数字组成。
20. isprintable
21. isspace 检测只包含空格键则为Ture,否则Flase
22. istitle 检测是否为标题化
str =‘This Is String Example Wow!!‘ str2 =‘this is string example wow!!‘ print(str.istitle()) print(str2.istitle()) True False
23. isupper 检测所有字母是否为大写的
*24. join 常用语句 分隔符，将所有元素合并成一个新的字符串
str.join(sequence) str = ‘-‘ seq = (‘a‘,‘b‘,‘c‘,‘d‘) #字符串序列 print (str.join(seq)) a-b-c-d
25. ljust 左对齐，填充字符（默认为空格）
str.ljust(width[, fillchar]) width -- 指定字符串长度。 fillchar -- 填充字符，默认为空格。 a = ‘this is string example....wow!!‘ print(a.ljust(50,‘#‘)) this is string example....wow!!###################
26. lower 转换所有大写为小写字母
27. lstrip 截掉左边空格
str.lstrip([chars]) chars --指定截取的字符。 a = ‘ this is string example....wow!!‘ b = ‘aaaaaathis is stringaaaaa‘ print(a.lstrip()) print(b.lstrip(‘a‘)) this is string example....wow!! this is stringaaaaa
28.maketrans 创建字符映射转换表
str.maketrans(intab, outtab) intab -- 字符串中要替代的字符组成的字符串。 outtab -- 相应的映射字符的字符串。 #!/usr/bin/python # -*- coding: UTF-8 -*- from string import maketrans # 必须调用 maketrans 函数。 intab = "aeiou" outtab = "12345" trantab = maketrans(intab, outtab) str = "this is string example....wow!!!"; print str.translate(trantab); th3s 3s str3ng 2x1mpl2....w4w!!!
29. partition 指定的分隔符将字符串分割，返回一个3元元组
str.partition(str) str : 指定的分隔符 a = ‘http://www.baidu.com/‘ print(a.partition(‘://‘)) (‘http‘, ‘://‘, ‘www.baidu.com/‘) #返回一个3元的元组，第一个为分隔符左边的子串，第二个为分隔符本身，第三个为分隔符右边的子串
**30. replace 替换
str.replace(old, new[, max]) old -- 将被替换的子字符串。 new -- 新字符串，用于替换old子字符串。 max -- 可选字符串, 替换不超过 max 次 str = ‘this is string example...wow!! this is really string‘ print(str.replace(‘is‘,‘was‘)) print(str.replace(‘is‘,‘was‘,3)) thwas was string example...wow!! thwas was really string thwas was string example...wow!! thwas is really string
时间： 2024-10-05 07:21:14