__format__
目录 一、__format__ 一、__format__ 自定制格式化字符串 date_dic = { 'ymd': '{0.year}:{0.month}:{0.day}', 'dmy': '{0.day}/{0.month}/{0.year}', 'mdy': '{0.month}-{0.day}-{0.year}', } class Date: def __init__(self, year, month, day): self.year = year self.month = month self.day = day def __format__(self, format_spec): # 默认打印ymd的{0.year}:{0.month}:{0.day}格式 if not format_spec or format_spec not in date_dic: format_spec = 'ymd' fmt = date_dic[format_spec] return fmt.format(self) d1 = Date(2016, 12, 29) print(format(d1)) 2016:12:29 print('{:mdy}'.format(d1)) 12-29-2016 来源: https://www.cnblogs.com/nickchen121/p