Ruby – Date/Time

Time.now : will give the time now…

%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

t = Time.now
t.strftime(“Printed on %m/%d/%Y”) #=> “Printed on 04/09/2003″
t.strftime(“at %I:%M%p”) #=> “at 08:56AM”

to create a new time stamp Time.mktime(yyyy,mm,dd,hh,mm,ss)

commonly used methods are Time.year,month,day,wday,yday,hour,min,sec,zone or the cannonical time.

Time.ctime,Time.utc(universal time,GMT),Time.dst?(daylight saving time),

You can use the normal compare eql?/<=>/ subtracting(gives in terms of seconds)/ you can add seconds .say if you want add 24 hours you say Time.now + 24 * 60 * 60

Date

Date.today: to get today’s date

Date.new(yyyy,mm,dd)

commonly used are to_s,succ,next,leap, to add and subtract just use + / – (it will done in terms of days). to add /subtract months use >> / <<.

downto/upto methods can be used for countdowns on the date object using another date object as parameter.. d1.upto(d2){ |d| block }

parsedate: require “parsedate.rb” p parsedate (“12/24/2008″)