时间格式

记录，以免以后找着麻烦

Format    Meaning
%a    The abbreviated weekday name (“Sun'’)
%A    The full weekday name (“Sunday'’)
%b    The abbreviated month name (“Jan'’)
%B    The full month name (“January'’)
%c    The preferred local date and time representation
%d    Day of the month (01..31)
%H    Hour of the day, 24-hour clock (00..23)
%I    Hour of the day, 12-hour clock (01..12)
%j    Day of the year (001..366)
%m    Month of the year (01..12)
%M    Minute of the hour (00..59)
%p    Meridian indicator (“AM'’ or “PM'’)
%S    Second of the minute (00..60)
%U    Week number of the current year, starting with the first Sunday as the first day of the first week (00..53)
%W    Week number of the current year, starting with the first Monday as the first day of the first week (00..53)
%w    Day of the week (Sunday is 0, 0..6)
%x    Preferred representation for the date alone, no time
%X    Preferred representation for the time alone, no date
%y    Year without a century (00..99)
%Y    Year with century
%Z    Time zone name
%%    Literal “%'’ character