自定制格式化方式format

自定制格式化方式format

# x='{0}{0}{0}'.format('dog')

#

# print(x)

# class Date:

#     def __init__(self,year,mon,day):

#         self.year=year

#         self.mon=mon

#         self.day=day

# d1=Date(2016,12,26)

#

# x='{0.year}{0.mon}{0.day}'.format(d1)

# y='{0.year}:{0.mon}:{0.day}'.format(d1)

# z='{0.mon}-{0.day}-{0.year}'.format(d1)

# print(x)

# print(y)

# print(z)

# x='{0.year}{0.mon}{0.day}'.format(d1)

# y='{0.year}:{0.mon}:{0.day}'

# z='{0.mon}-{0.day}-{0.year}'

format_dic={

    'ymd':'{0.year}{0.mon}{0.day}',

    'm-d-y':'{0.mon}-{0.day}-{0.year}',

    'y:m:d':'{0.year}:{0.mon}:{0.day}'

}

class Date:

    def __init__(self,year,mon,day):

        self.year=year

        self.mon=mon

        self.day=day

    def __format__(self, format_spec):

        print('我执行啦')

        print('--->',format_spec)

        if not format_spec or format_spec not in format_dic:

            format_spec='ymd'

        fm=format_dic[format_spec]

        return fm.format(self)

d1=Date(2016,12,26)

# format(d1) #d1.__format__()

# print(format(d1))

print(format(d1,'ymd'))

print(format(d1,'y:m:d'))

print(format(d1,'m-d-y'))

print(format(d1,'m-d:y'))

print('===========>',format(d1,'asdfasdfsadfasdfasdfasdfasdfasdfasdfasdfasdfasdfasd'))