Help on built-in function format in module __builtin__:
format(...)
format(value[, format_spec]) -> string
Returns value.__format__(format_spec)
format_spec defaults to ""
format(value[, format_spec])
Convert a value to a “formatted” representation, as controlled by format_spec. The interpretation of format_spec will depend on the type of the value argument, however there is a standard formatting syntax that is used by most built-in types: Format Specification Mini-Language.
Note format(value, format_spec) merely calls value.__format__(format_spec).
中文说明：
格式化字符串
通过位置
>>> ‘{0},{1}‘.format(‘kzc‘,18)
‘kzc,18‘
>>> ‘{1},{0}‘.format(‘kzc‘,18)
‘18,kzc‘
>>> ‘{},{}‘.format(‘kzc‘,18)
‘kzc,18‘
>>> ‘{0},{1},{1}‘.format(‘kzc‘,18)
‘kzc,18,18‘
通过关键字参数
>>> ‘{name},{age}‘.format(age=18,name=‘kzc‘)
‘kzc,18‘
通过对象属性
>>> class Person:
... def __init__(self,name,age):
... self.name,self.age = name,age
... def __str__(self):
... return ‘This guy is {self.name},is {self.age} old‘.format(self=self)
...
>>> str(Person(‘kzc‘,18))
‘This guy is kzc,is 18 old‘
通过下标
>>> p=[‘kzc‘,18]
>>> ‘{0[0]},{0[1]}‘.format(p)
‘kzc,18‘
填充与对齐
^、<、>分别是居中、左对齐、右对齐，后面带宽度
:号后面带填充的字符，只能是一个字符，不指定的话默认是用空格填充
>>> ‘{:>8}‘.format(‘732‘)
‘ 732‘
>>> ‘{:6>8}‘.format(‘732‘)
‘66666732‘
>>> ‘{:a<8}‘.format(‘732‘)
‘732aaaaa‘
精度与类型f
>>> ‘{:.2f}‘.format(435.62882)
‘435.63‘
>>> ‘{:b}‘.format(67)
‘1000011‘
>>> ‘{:d}‘.format(67)
‘67‘
>>> ‘{:o}‘.format(67)
‘103‘
>>> ‘{:x}‘.format(67)
‘43‘
>>> ‘{:,}‘.format(543721318713)
‘543,721,318,713‘