原文：https://blog.csdn.net/drcwr/article/details/50971637
%% a literal % 一个文字
%a locale's abbreviated weekday name (e.g., Sun) 语言环境的缩写工作日的名字
%A locale's full weekday name (e.g., Sunday) 语言环境的完整工作日的名字
%b locale's abbreviated month name (e.g., Jan) 语言环境的缩写月的名字
%B locale's full month name (e.g., January) 语言环境是完整月的名字
%c locale's date and time (e.g., Thu Mar 3 23:05:25 2005) 区域设置的日期和时间
%C century; like %Y, except omit last two digits (e.g., 20) 世纪;像% Y,只不过省略最后两位数
%d day of month (e.g., 01) 某天
%D date; same as %m/%d/%y 日期；月日年
%e day of month, space padded; same as %_d 某天 类似%_d
%F full date; same as %Y-%m-%d 完整日期 ，年月日
%g last two digits of year of ISO week number (see %G)
%G year of ISO week number (see %V); normally useful only with %V
%h same as %b
%H hour (00..23)
%I hour (01..12)
%j day of year (001..366)
%k hour, space padded ( 0..23); same as %_H
%l hour, space padded ( 1..12); same as %_I
%m month (01..12)
%M minute (00..59)
%n a newline
%N nanoseconds (000000000..999999999)
%p locale's equivalent of either AM or PM; blank if not known
%P like %p, but lower case
%r locale's 12-hour clock time (e.g., 11:11:04 PM)
%R 24-hour hour and minute; same as %H:%M
%s seconds since 1970-01-01 00:00:00 UTC
%S second (00..60)
%t a tab
%T time; same as %H:%M:%S
%u day of week (1..7); 1 is Monday
%U week number of year, with Sunday as first day of week (00..53)
%V ISO week number, with Monday as first day of week (01..53)
%w day of week (0..6); 0 is Sunday
%W week number of year, with Monday as first day of week (00..53)
%x locale's date representation (e.g., 12/31/99)
%X locale's time representation (e.g., 23:13:48)
%y last two digits of year (00..99)
%Y year
%z +hhmm numeric time zone (e.g., -0400)
%:z +hh:mm numeric time zone (e.g., -04:00)
%::z +hh:mm:ss numeric time zone (e.g., -04:00:00) + hh:mm:ss数字时区
%:::z numeric time zone with : to necessary precision (e.g., -04, +05:30) 模时区:必要的精度
%Z alphabetic time zone abbreviation (e.g., EDT) 字母时区缩写
哈哈，懒得翻译了，需要时再翻译吧，我这边最常用的就是年月日，时分秒的格式，其他的了解就行。