Python之字符串操作
def capitalize(self): 首字母大写 def casefold(self): 把字符串全变小写 >> > c = 'Alex Li' >> > c.casefold() 'alex li' def center(self, width, fillchar=None): >> > c.center(50, "-") '---------------------Alex Li----------------------' def count(self, sub, start=None, end=None): """ S.count(sub[, start[, end]]) -> int >>> s = "welcome to apeland" >>> s.count('e') 3 >>> s.count('e',3) 2 >>> s.count('e',3,-1) 2 def encode(self, encoding='utf-8', errors='strict'): """ 编码,日后讲 def endswith(self, suffix, start=None, end=None): >> > s = "welcome to apeland" >> > s.endswith("land") 判断以什么结尾 True def find(self, sub, start=None, end=None): """ 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(self, *args, **kwargs): # known special case of str.format >> > s = "Welcome {0} to Apeland,you are No.{1} user." >> > s.format("Eva", 9999) 'Welcome Eva to Apeland,you are No.9999 user.' >> > s1 = "Welcome {name} to Apeland,you are No.{user_num} user." >> > s1.format(name="Alex", user_num=999) 'Welcome Alex to Apeland,you are No.999 user.' def format_map(self, mapping): """ S.format_map(mapping) -> str Return a formatted version of S, using substitutions from mapping. The substitutions are identified by braces ('{' and '}'). """ 讲完dict再讲这个 def index(self, sub, start=None, end=None): """ S.index(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. Raises ValueError when the substring is not found. """ def isdigit(self): """ 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): """ 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. """ 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. """ 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. """ def join(self, iterable): """ S.join(iterable) -> str Return a string which is the concatenation of the strings in the iterable. The separator between elements is S. """ >>> n = ['alex','jack','rain'] >>> '|'.join(n) 'alex|jack|rain' def ljust(self, width, fillchar=None): """ S.ljust(width[, fillchar]) -> str Return S left-justified in a Unicode string of length width. Padding is done using the specified fill character (default is a space). """ return "" def lower(self): """ S.lower() -> str Return a copy of the string S converted to lowercase. """ return "" def lstrip(self, chars=None): """ S.lstrip([chars]) -> str Return a copy of the string S with leading whitespace removed. If chars is given and not None, remove characters in chars instead. """ return "" def replace(self, old, new, count=None): """ S.replace(old, new[, count]) -> str Return a copy of 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 rjust(self, width, fillchar=None): """ S.rjust(width[, fillchar]) -> str Return S right-justified in a string of length width. Padding is done using the specified fill character (default is a space). """ return "" def rsplit(self, sep=None, maxsplit=-1): """ S.rsplit(sep=None, maxsplit=-1) -> list of strings Return a list of the words in 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, any whitespace string is a separator. """ return [] def rstrip(self, chars=None): """ S.rstrip([chars]) -> str Return a copy of the string S with trailing whitespace removed. If chars is given and not None, remove characters in chars instead. """ return "" def split(self, sep=None, maxsplit=-1): """ S.split(sep=None, maxsplit=-1) -> list of strings Return a list of the words in 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 startswith(self, prefix, start=None, end=None): """ 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): """ S.strip([chars]) -> str 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. """ return "" def swapcase(self): """ S.swapcase() -> str Return a copy of S with uppercase characters converted to lowercase and vice versa. """ return "" def upper(self): """ S.upper() -> str Return a copy of S converted to uppercase. """ return "" def zfill(self, width): """ S.zfill(width) -> str 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 ""