Python中的string模块的学习

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>>> import string >>> string.ascii_letters 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ' >>> string.ascii_lowercase 'abcdefghijklmnopqrstuvwxyz' >>> string.ascii_uppercase 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' >>> string.digits '0123456789' >>> string.hexdigits '0123456789abcdefABCDEF' >>> string.letters 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz' >>> string.lowercase 'abcdefghijklmnopqrstuvwxyz' >>> string.uppercase 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' >>> string.octdigits '01234567' >>> string.punctuation '!"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~' >>> string.printable '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~ \t\n\r\x0b\x0c' >>> string.whitespace '\t\n\x0b\x0c\r

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>>> '{0}, {1}, {2}'.format('a', 'b', 'c') 'a, b, c' >>> '{}, {}, {}'.format('a', 'b', 'c')  # 2.7+ only 'a, b, c' >>> '{2}, {1}, {0}'.format('a', 'b', 'c') 'c, b, a' >>> '{2}, {1}, {0}'.format(*'abc')      # unpacking argument sequence 'c, b, a' >>> '{0}{1}{0}'.format('abra', 'cad')   # arguments' indices can be repeated 'abracadabra'   >>> 'Coordinates: {latitude}, {longitude}'.format(latitude='37.24N', longitude='-115.81W') 'Coordinates: 37.24N, -115.81W' >>> coord = {'latitude': '37.24N', 'longitude': '-115.81W'} >>> 'Coordinates: {latitude}, {longitude}'.format(**coord) 'Coordinates: 37.24N, -115.81W'   >>> c = 3-5j >>> ('The complex number {0} is formed from the real part {0.real} ' ...  'and the imaginary part {0.imag}.').format(c) 'The complex number (3-5j) is formed from the real part 3.0 and the imaginary part -5.0.' >>> class Point(object): ...     def __init__(self, x, y): ...         self.x, self.y = x, y ...     def __str__(self): ...         return 'Point({self.x}, {self.y})'.format(self=self) ... >>> str(Point(4, 2)) 'Point(4, 2)   >>> coord = (3, 5) >>> 'X: {0[0]};  Y: {0[1]}'.format(coord) 'X: 3;  Y: 5'   >>> "repr() shows quotes: {!r}; str() doesn't: {!s}".format('test1', 'test2') "repr() shows quotes: 'test1'; str() doesn't: test2"   >>> '{:<30}'.format('left aligned') 'left aligned                  ' >>> '{:>30}'.format('right aligned') '                 right aligned' >>> '{:^30}'.format('centered') '           centered           ' >>> '{:*^30}'.format('centered')  # use '*' as a fill char '***********centered***********'   >>> '{:+f}; {:+f}'.format(3.14, -3.14)  # show it always '+3.140000; -3.140000' >>> '{: f}; {: f}'.format(3.14, -3.14)  # show a space for positive numbers ' 3.140000; -3.140000' >>> '{:-f}; {:-f}'.format(3.14, -3.14)  # show only the minus -- same as '{:f}; {:f}' '3.140000; -3.140000'   >>> # format also supports binary numbers >>> "int: {0:d};  hex: {0:x};  oct: {0:o};  bin: {0:b}".format(42) 'int: 42;  hex: 2a;  oct: 52;  bin: 101010' >>> # with 0x, 0o, or 0b as prefix: >>> "int: {0:d};  hex: {0:#x};  oct: {0:#o};  bin: {0:#b}".format(42) 'int: 42;  hex: 0x2a;  oct: 0o52;  bin: 0b101010'   >>> '{:,}'.format(1234567890) '1,234,567,890'   >>> points = 19.5 >>> total = 22 >>> 'Correct answers: {:.2%}.'.format(points/total) 'Correct answers: 88.64%'   >>> import datetime >>> d = datetime.datetime(2010, 7, 4, 12, 15, 58) >>> '{:%Y-%m-%d %H:%M:%S}'.format(d) '2010-07-04 12:15:58'   >>> for align, text in zip('<^>', ['left', 'center', 'right']): ...     '{0:{fill}{align}16}'.format(text, fill=align, align=align) ... 'left<<<<<<<<<<<<' '^^^^^center^^^^^' '>>>>>>>>>>>right' >>> >>> octets = [192, 168, 0, 1] >>> '{:02X}{:02X}{:02X}{:02X}'.format(*octets) 'C0A80001' >>> int(_, 16) 3232235521 >>> >>> width = 5 >>> for num in range(5,12): ...     for base in 'dXob': ...         print '{0:{width}{base}}'.format(num, base=base, width=width), ...     print ...     5     5     5   101     6     6     6   110     7     7     7   111     8     8    10  1000     9     9    11  1001    10     A    12  1010    11     B    13  1011   >>> from string import Template >>> s = Template('$who likes $what') >>> s.substitute(who='tim', what='kung pao') 'tim likes kung pao' >>> d = dict(who='tim') >>> Template('Give $who $100').substitute(d) Traceback (most recent call last): [...] ValueError: Invalid placeholder in string: line 1, col 10 >>> Template('$who likes $what').substitute(d) Traceback (most recent call last): [...] KeyError: 'what' >>> Template('$who likes $what').safe_substitute(d) 'tim likes $what'

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string.capitalize(word) 返回一个副本，首字母大写 >>> string.capitalize("hello") 'Hello' >>> string.capitalize("hello world") 'Hello world'   >>> string.split("asdadada asdada") ['asdadada', 'asdada']   >>> string.strip("              adsd         ") 'adsd' >>> string.rstrip("              adsd         ") '              adsd' >>> string.lstrip("              adsd         ") 'adsd         '   string.swapcase(s) 小写变大写，大写变小写 >>> string.swapcase("Helloo") 'hELLOO'   >>> string.ljust("ww",20) 'ww                  ' >>> string.rjust('ww',20) '                  ww' >>> string.center('ww',20) '         ww         ' string.zfill(s, width) Pad a numeric string on the left with zero digits until the given width is reached. Strings starting with a sign are handled correctly. >>> string.zfill('ww',20) '000000000000000000ww'