python中强大的format函数实例详解

#通过位置
print \'{0},{1}\'.format(\'chuhao\',20)
print \'{},{}\'.format(\'chuhao\',20)
print \'{1},{0},{1}\'.format(\'chuhao\',20)
#通过关键字参数
print \'{name},{age}\'.format(age=18,name=\'chuhao\')
class Person:
  def __init__(self,name,age):
    self.name = name
    self.age = age
  def __str__(self):
    return \'This guy is {self.name},is {self.age} old\'.format(self=self)
print str(Person(\'chuhao\',18))
#通过映射 list
a_list = [\'chuhao\',20,\'china\']
print \'my name is {0[0]},from {0[2]},age is {0[1]}\'.format(a_list)
#my name is chuhao,from china,age is 20
#通过映射 dict
b_dict = {\'name\':\'chuhao\',\'age\':20,\'province\':\'shanxi\'}
print \'my name is {name}, age is {age},from {province}\'.format(**b_dict)
#my name is chuhao, age is 20,from shanxi
#填充与对齐
print \'{:>8}\'.format(\'189\')
#   189
print \'{:0>8}\'.format(\'189\')
#00000189
print \'{:a>8}\'.format(\'189\')
#aaaaa189
#精度与类型f
#保留两位小数
print \'{:.2f}\'.format(321.33345)
#321.33
#用来做金额的千位分隔符
print \'{:,}\'.format(1234567890)
#1,234,567,890
#其他类型 主要就是进制了，b、d、o、x分别是二进制、十进制、八进制、十六进制。
print \'{:b}\'.format(18) #二进制 10010
print \'{:d}\'.format(18) #十进制 18
print \'{:o}\'.format(18) #八进制 22
print \'{:x}\'.format(18) #十六进制12